WORLD
DRUG
REPORT
2018
4
DRUGS AND AGE
Drugs and associated issues among
young people and older people
9 789211 483048
ISBN 978-92-1-148304-8
© United Nations, June 2018. All rights reserved worldwide.
ISBN: 978-92-1-148304-8
eISBN: 978-92-1-045058-4
United Nations publication, Sales No. E.18.XI.9
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Comments on the report are welcome and can be sent to:
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1
PREFACE
Drug treatment and health services continue to fall
short: the number of people suffering from drug use
disorders who are receiving treatment has remained
low, just one in six. Some 450,000 people died in
2015 as a result of drug use. Of those deaths,
167,750 were a direct result of drug use disorders,
in most cases involving opioids.
These threats to health and well-being, as well as to
security, safety and sustainable development,
demand an urgent response.
The outcome document of the special session of the
General Assembly on the world drug problem held
in 2016 contains more than 100 recommendations
on promoting evidence-based prevention, care and
other measures to address both supply and demand.
We need to do more to advance this consensus,
increasing support to countries that need it most
and improving international cooperation and law
enforcement capacities to dismantle organized crimi-
nal groups and stop drug trafficking.
The United Nations Office on Drugs and Crime
(UNODC) continues to work closely with its
United Nations partners to assist countries in imple-
menting the recommendations contained in the
outcome document of the special session, in line
with the international drug control conventions,
human rights instruments and the 2030 Agenda for
Sustainable Development.
In close cooperation with the World Health Organi-
zation, we are supporting the implementation of
the International Standards on Drug Use Prevention
and the international standards for the treatment of
drug use disorders, as well as the guidelines on treat-
ment and care for people with drug use disorders in
contact with the criminal justice system.
The World Drug Report 2018 highlights the impor-
tance of gender- and age-sensitive drug policies,
exploring the particular needs and challenges of
women and young people. Moreover, it looks into
Both the range of drugs and drug markets are
expanding and diversifying as never before. The
findings of this year’s World Drug Report make clear
that the international community needs to step up
its responses to cope with these challenges.
We are facing a potential supply-driven expansion
of drug markets, with production of opium and
manufacture of cocaine at the highest levels ever
recorded. Markets for cocaine and methampheta-
mine are extending beyond their usual regions and,
while drug trafficking online using the darknet con-
tinues to represent only a fraction of drug trafficking
as a whole, it continues to grow rapidly, despite
successes in shutting down popular trading
platforms.
Non-medical use of prescription drugs has reached
epidemic proportions in parts of the world. The
opioid crisis in North America is rightly getting
attention, and the international community has
taken action. In March 2018, the Commission on
Narcotic Drugs scheduled six analogues of fentanyl,
including carfentanil, which are contributing to the
deadly toll. This builds on the decision by the
Commission at its sixtieth session, in 2017, to place
two precursor chemicals used in the manufacture
of fentanyl and an analogue under international
control.
However, as this World Drug Report shows, the prob-
lems go far beyond the headlines. We need to raise
the alarm about addiction to tramadol, rates of
which are soaring in parts of Africa. Non-medical
use of this opioid painkiller, which is not under
international control, is also expanding in Asia. The
impact on vulnerable populations is cause for seri-
ous concern, putting pressure on already strained
health-care systems.
At the same time, more new psychoactive substances
are being synthesized and more are available than
ever, with increasing reports of associated harm and
fatalities.
2
WORLD DRUG REPORT 2018
Next year, the Commission on Narcotic Drugs will
host a high-level ministerial segment on the 2019
target date of the 2009 Political Declaration and
Plan of Action on International Cooperation
towards an Integrated and Balanced Strategy to
Counter the World Drug Problem. Preparations are
under way. I urge the international community to
take this opportunity to reinforce cooperation and
agree upon effective solutions.
Yury Fedotov
Executive Director
United Nations Office on Drugs and Crime
increased drug use among older people, a develop-
ment requiring specific treatment and care.
UNODC is also working on the ground to promote
balanced, comprehensive approaches. The Office
has further enhanced its integrated support to
Afghanistan and neighbouring regions to tackle
record levels of opiate production and related secu-
rity risks. We are supporting the Government of
Colombia and the peace process with the Revolu-
tionary Armed Forces of Colombia (FARC) through
alternative development to provide licit livelihoods
free from coca cultivation.
Furthermore, our Office continues to support efforts
to improve the availability of controlled substances
for medical and scientific purposes, while prevent-
ing misuse and diversion – a critical challenge if we
want to help countries in Africa and other regions
come to grips with the tramadol crisis.
3
CONTENTS
BOOKLET 1
EXECUTIVE SUMMARY — CONCLUSIONS AND POLICY IMPLICATIONS
BOOKLET 2
GLOBAL OVERVIEW OF DRUG DEMAND AND SUPPLY
Latest trends, cross-cutting issues
BOOKLET 3
ANALYSIS OF DRUG MARKETS
Opioids, cocaine, cannabis, synthetic drugs
BOOKLET 4
DRUGS AND AGE
Drugs and associated issues among young people and older people
BOOKLET 5
WOMEN AND DRUGS
Drug use, drug supply and their consequences
PREFACE ...................................................................................................... 1
EXPLANATORY NOTES ................................................................................ 5
KEY FINDINGS ............................................................................................. 6
INTRODUCTION ........................................................................................... 9
A. DRUG USE AMONG YOUNG PEOPLE AND OLDER PEOPLE ...................11
Trends in age demographics ...........................................................................................................11
Extent of drug use is higher among young people than among older people .................................11
B. DRUGS AND YOUNG PEOPLE ................................................................15
Patterns of drug use among young people .....................................................................................16
Pathways to substance use disorders ...............................................................................................22
Young people and the supply chain ...............................................................................................40
C. DRUGS AND OLDER PEOPLE .................................................................46
Changes in the extent of drug use among older people .................................................................47
What factors might lie behind the increase in the extent of drug use? ...........................................49
Drug treatment among older people who use drugs ......................................................................52
Drug-related deaths among older people who use drugs ................................................................54
GLOSSARY .................................................................................................. 57
REGIONAL GROUPINGS ..............................................................................59
4
WORLD DRUG REPORT 2018
Acknowledgements
The World Drug Report 2018 was prepared by the Research and Trend Analysis Branch, Division for
Policy Analysis and Public Affairs, United Nations Office on Drugs and Crime, under the supervision
of Jean-Luc Lemahieu, Director of the Division, and Angela Me, Chief of the Research and Trend
Analysis Branch.
General coordination and content overview
Chloé Carpentier
Angela Me
Analysis and drafting
Philip Davis
Diana Fishbein
Alejandra Sánchez Inzunza
Theodore Leggett
Kamran Niaz
Thomas Pietschmann
José Luis Pardo Veiras
Editing
Joseph Boyle
Jonathan Gibbons
Graphic design and production
Anja Korenblik
Suzanne Kunnen
Kristina Kuttnig
Coordination
Francesca Massanello
Administrative support
Anja Held
Iulia Lazar
Jonathan Caulkins
Paul Griffiths
Marya Hynes
Vicknasingam B. Kasinather
Letizia Paoli
Charles Parry
Peter Reuter
Francisco Thoumi
Alison Ritter
In memoriam
Brice de Ruyver
Review and comments
The World Drug Report 2018 benefited from the expertise of and invaluable contributions from
UNODC colleagues in all divisions.
The Research and Trend Analysis Branch acknowledges the invaluable contributions and advice
provided by the World Drug Report Scientific Advisory Committee:
The research for booklet 4 was made possible by the generous contribution of Germany
(German Agency for International Cooperation (GIZ)).
5
EXPLANATORY NOTES
The boundaries and names shown and the designa-
tions used on maps do not imply official endorsement
or acceptance by the United Nations. A dotted line
represents approximately the line of control in
Jammu and Kashmir agreed upon by India and Paki-
stan. The final status of Jammu and Kashmir has
not yet been agreed upon by the parties. Disputed
boundaries (China/India) are represented by cross-
hatch owing to the difficulty of showing sufficient
detail.
The designations employed and the presentation of
the material in the World Drug Report do not imply
the expression of any opinion whatsoever on the
part of the Secretariat of the United Nations con-
cerning the legal status of any country, territory, city
or area, or of its authorities or concerning the delimi-
tation of its frontiers or boundaries.
Countries and areas are referred to by the names
that were in official use at the time the relevant data
were collected.
All references to Kosovo in the World Drug Report,
if any, should be understood to be in compliance
with Security Council resolution 1244 (1999).
Since there is some scientific and legal ambiguity
about the distinctions between “drug use”, “drug
misuse” and “drug abuse”, the neutral terms “drug
use” and “drug consumption” are used in the World
Drug Report. The term “misuse” is used only to
denote the non-medical use of prescription drugs.
All uses of the word “drug” in the World Drug Report
refer to substances controlled under the international
drug control conventions.
All analysis contained in the World Drug Report is
based on the official data submitted by Member
States to the United Nations Office on Drugs and
Crime through the annual report questionnaire
unless indicated otherwise.
The data on population used in the World Drug
Report are taken from: World Population Prospects:
The 2017 Revision (United Nations, Department of
Economic and Social Affairs, Population Division).
References to dollars ($) are to United States dollars,
unless otherwise stated.
References to tons are to metric tons, unless other-
wise stated.
The following abbreviations have been used in the
present booklet:
EMCDDA
European Monitoring Centre for
Drugs and Drug Addiction
LSD Lysergic acid diethylamide
GHB gamma-Hydroxybutyric acid
MDMA 3,4-methylenedioxymethamphetamine
UNICEF United Nations Children’s Fund
WHO World Health Organization
UNODC United Nations Office on Drugs
and Crime
INCB International Narcotics Control Board
Europol European Union Agency for Law
Enforcement Cooperation
KEY FINDINGS
Drug use and associated health conse-
quences are highest among young people
Surveys on drug use among the general population
show that the extent of drug use among young
people remains higher than that among older
people, although there are some exceptions associ-
ated with the traditional use of drugs such as opium
or khat. Most research suggests that early (12–14
years old) to late (15–17 years old) adolescence is a
critical risk period for the initiation of substance
use and that substance use may peak among young
people aged 18–25 years.
Cannabis is a common drug of choice for
young people
There is evidence from Western countries that the
perceived easy availability of cannabis, coupled with
perceptions of a low risk of harm, makes the drug
among the most common substances whose use is
initiated in adolescence. Cannabis is often used in
conjunction with other substances and the use of
other drugs is typically preceded by cannabis use.
Two extreme typologies of drug use
among young people: club drugs in
nightlife settings; and inhalants among
street children
Drug use among young people differs from country
to country and depends on the social and economic
circumstances of those involved.
Two contrasting settings illustrate the wide range
of circumstances that drive drug use among young
people. On the one hand, drugs are used in recrea-
tional settings to add excitement and enhance the
experience; on the other hand, young people living
in extreme conditions use drugs to cope with their
difficult circumstances.
The typologies of drugs used in these two different
settings are quite different. Club drugs such as
“ecstasy”, methamphetamine, cocaine, ketamine,
LSD and GHB are used in high-income countries,
originally in isolated “rave” scenes but later in
settings ranging from college bars and house parties
to concerts. The use of such substances is reportedly
much higher among young people. Among young
people living on the street, the most commonly used
drugs are likely to be inhalants, which can include
paint thinner, petrol, paint, correction fluid and
glue.
Many street children are exposed to physical and
sexual abuse, and substance use is part of their
coping mechanism in the harsh environment they
are exposed to on the streets. The substances they
use are frequently selected for their low price, legal
and widespread availability and ability to rapidly
induce a sense of euphoria.
Young people’s path to harmful use of
substances is complex
The path from initiation to harmful use of sub-
stances among young people is influenced by factors
that are often out of their control. Factors at the
personal level (including behavioural and mental
health, neurological developments and gene varia-
tions resulting from social influences), the micro
level (parental and family functioning, schools and
peer influences) and the macro level (socioeconomic
and physical environment) can render adolescents
vulnerable to substance use. These factors vary
between individuals and not all young people are
equally vulnerable to substance use. No factor alone
is sufficient to lead to the use of substances and, in
many instances, these influences change over time.
Overall, it is the critical combination of the risk
factors that are present and the protective factors
that are absent at a particular stage in a young per-
son’s life that makes the difference in their
susceptibility to drug use. Early mental and behav-
ioural health problems, poverty, lack of
opportunities, isolation, lack of parental involve-
ment and social support, negative peer influences
and poorly equipped schools are more common
among those who develop problems with substance
use than among those who do not.
7
4
Harmful use of substances has multiple direct effects
on adolescents. The likelihood of unemployment,
physical health problems, dysfunctional social rela-
tionships, suicidal tendencies, mental illness and
even lower life expectancy is increased by substance
use in adolescence. In the most serious cases, harm-
ful use of drugs can lead to a cycle in which damaged
socioeconomic standing and ability to develop rela-
tionships feed substance use.
Many young people are involved in the
drug supply chain due to poverty and lack
of opportunities for social and economic
advancement
Young people are also known to be involved in the
cultivation, manufacturing and production of and
trafficking in drugs. In the absence of social and
economic opportunities, young people may deal
drugs to earn money or to supplement meagre wages.
Young people affected by poverty or in other vulner-
able groups, such as immigrants, may be recruited
by organized crime groups and coerced into working
in drug cultivation, production, trafficking and
local-level dealing. In some environments, young
people become involved in drug supply networks
because they are looking for excitement and a means
to identify with local groups or gangs. Organized
crime groups and gangs may prefer to recruit chil-
dren and young adults for drug trafficking for two
reasons: the first is the recklessness associated with
younger age groups, even when faced with the police
or rival gangs; the second is their obedience. Young
people involved in the illicit drug trade in interna-
tional markets are often part of large organized crime
groups and are used mainly as “mules”, to smuggle
illegal substances across borders.
Increases in rates of drug use among older
people are partly explained by ageing
cohorts of drug users
Drug use among the older generation (aged 40 years
and older) has been increasing at a faster rate than
among those who are younger, according to the lim-
ited data available, which are mainly from Western
countries.
People who went through adolescence at a time
when drugs were popular and widely available are
more likely to have tried drugs and, possibly, to have
continued using them, according to a study in the
United States. This pattern fits in particular the so-
called “baby boomer” generation in Western Europe
and North America. Born between 1946 and 1964,
baby boomers had higher rates of substance use
during their youth than previous cohorts; a signifi-
cant proportion continued to use drugs and, now
that they are over 50, this use is reflected in the data.
In Europe, another cohort effect can be gleaned from
data on those seeking treatment for opioid use.
Although the number of opioid users entering treat-
ment is declining, the proportion who were aged
over 40 increased from one in five in 2006 to one in
three in 2013. Overdose deaths reflect a similar trend:
they increased between 2006 and 2013 for those
aged 40 and older but declined for those aged under
40. The evidence points to a large cohort of ageing
opioid users who started injecting heroin during the
heroin “epidemics” of the 1980s and 1990s.
Older people who use drugs require
tailored services, but few treatment
programmes address their specific needs
Older drug users may often have multiple physical
and mental health problems, making effective drug
treatment more challenging, yet little attention has
been paid to drug use disorders among older people.
There were no explicit references to older drug users
in the drug strategies of countries in Europe in 2010
and specialized treatment and care programmes for
older drug users are rare in the region; most initia-
tives are directed towards younger people.
Older people who use drugs account
for an increasing share of deaths directly
caused by drug use
Globally, deaths directly caused by drug use increased
by 60 per cent from 2000 to 2015. People over the
age of 50 accounted for 39 per cent of the deaths
related to drug use disorders in 2015. However, the
proportion of older people reflected in the statistics
has been rising: in 2000, older people accounted for
just 27 per cent of deaths from drug use disorders.
About 75 per cent of deaths from drug use disorders
among those aged 50 and older are linked to the
use of opioids. The use of cocaine and the use of
amphetamines each account for about 6 per cent;
the use of other drugs makes up the remaining 13
per cent.
9
INTRODUCTION
Substance use
initiation
Positive physical, social
and mental health
Harmful use
of substances
P
r
o
t
e
c
t
i
v
e
f
a
c
t
o
r
s
R
i
s
k
f
a
c
t
o
r
s
• Trauma and childhood
adversity
- child abuse and neglect
• Mental health problems
• Poverty
• Peer substance use and
drug availability
• Negative school climate
• Sensation seeking
Protective factors and risk factors for substance use
• Caregiver involvement
and monitoring
• Health and neurological
development:
- coping skills
- emotional regulation
• Physical safety and
social inclusion
• Safe neighbourhoods
• Quality school environment
Substance
use disorders
This booklet constitutes the fourth part of the World
Drug Report 2018 and is the first of two thematic
booklets focusing on specific population groups. In
this booklet, the focus is on drug issues affecting
young and older people.
Section A provides an overview of how the extent
and patterns of drug use vary across different age
groups, using examples from selected countries. Sec-
tion B contains a discussion of three aspects of drug
use among young people. Based on a review of the
scientific literature, the section describes the wide
range of patterns of drug use among young people,
including the use of inhalants among street children
and drug use in nightlife settings. Next, there is a
discussion of the link between child and youth devel-
opment and the factors that determine pathways to
substance use and related problems, as well as the
social and health consequences of drug use among
young people. The final part of the section contains
a discussion of how the lives of young people are
affected by illicit crop cultivation, drug production
and trafficking in drugs.
Section C is focused on older people who use drugs.
It describes the increases in the extent of drug use
among older people that have been observed over
the past decade or so in some countries. The pos-
sible factors that might help explain those increases
are briefly explored. The particular issues faced by
older people with drug use disorders in relation to
drug treatment and care are also discussed. Finally,
information on deaths due to drug use disorders
illustrates the severe health impact of drug use on
older people.
11
4
DRUGS AND AGE A. Drug use among young people and older people
Extent of drug use is higher among
young people than among older
people
Surveys on drug use among the general population
consistently show that the extent of drug use among
older people remains lower than that among young
people. Data show that peak levels of drug use are
seen among those aged 18–25. This is broadly the
situation observed in countries in most regions and
for most drug types.
The extent of drug use among young people, in
particular past-year and past-month prevalence,
which are indicators of recent and regular use,
remains much higher than that among older people.
However, lifetime prevalence, which is an indicator
of the extent of exposure of the general population
to drugs, remains higher among older people than
among young people for the use of substances that
have been on the market for decades. Conversely,
the use of substances that have emerged more
recently or have infiltrated certain lifestyles are
reportedly much higher among young people. One
such example is “ecstasy”, which has low levels of
lifetime use and hardly any current use among older
people, but high levels of lifetime use among young
people.
2 United Nations, Department of Economic and Social
Affairs, Population Division, “World population prospects:
the 2017 revision, key findings and advance tables”, Work-
ing paper No. ESA/P/WP/248 (New York, 2017).
A. DRUG USE AMONG
YOUNG PEOPLE AND
OLDER PEOPLE
Trends in age demographics
The population in many parts of the world is rela-
tively young. In 2016, more than 4 in every 10
people worldwide were younger than 25 years old,
26 per cent were aged 0–14 years and 16 per cent
were aged 15–24 years. Europe was the region with
the lowest proportion of its population under 25
(27 per cent) and Africa was the region with the
highest proportion (60 per cent). However, in all
regions, the proportion of the population aged
15–24 is projected to decline by 2050.
1
On the other hand, in recent years, gains in life
expectancy have been achieved in all regions, with
life expectancy globally projected to increase by 10
per cent over the next generation or so, from 71
years (2010–2015) to 77 years (2045–2050).
2
As a
result, between 2016 and 2050, the number of
people aged 50 and older is expected to almost
double. By 2050, one third or more of the popula-
tions of all regions, except for Africa, will be aged
50 or older.
1 United Nations, Department of Economic and Social
Affairs, Population Division, World Population Prospects
database, 2017 revision.
Fig. 1
Proportion of population aged 15–24 years and aged 50 years or older, 1980–2050
Source: United Nations, Department of Economic and Social Affairs, Population Division, World Population Prospects database,
2017 revision.
0
10
20
30
40
50
1980
1990
2000
2010
2020
2030
2040
2050
Proportion of population aged 50 and older
(percentage)
Latin America and the Caribbean
North America
Oceania
0
5
10
15
20
25
1980
1990
2000
2010
2020
2030
2040
2050
Proportion of population aged 15-24
(percentage)
World
Afr ic a
Asia
Europe
0
5
10
15
20
25
1980
1990
2000
2010
2020
2030
2040
2050
Percentage
World
Afr ic a
Asia
Europe
0
10
20
30
40
50
1980
1990
2000
2010
2020
2030
2040
2050
Percentage
Latin America and the Caribbean
North America
Oceania
15–24 years
50 years and older
12
WORLD DRUG REPORT 2018
past-month prevalence are indicators of current
levels of drug use in that population.
Given the paucity of drug use survey data from dif-
ferent regions, as well as the different measures of
prevalence and age groups used in the surveys avail-
able, it is difficult to construct a global comparison
of drug use between young people and older people.
In the following paragraphs, therefore, examples from
different countries and regions are presented to illus-
trate the extent of and compare drug use among the
different age groups in those countries and regions.
In all the regions for which data could be analysed
by age, current drug use is much higher among
young people than older people. People aged over
40 generally have different patterns of drug use than
young people, except when it comes to substances
such as opium and khat, which have a long tradi-
tion of use in particular societies or cultures. Older
people are typically not exposed as much as young
people to new drugs that enter the market and they
tend to follow the drug use patterns that were initi-
ated during their youth.
Europe
Data for the 28 States members of the European
Union, plus Norway and Turkey, show that the life-
time use in those countries of amphetamines and
“ecstasy” is between two and three times higher
among those aged under 35 than among older
people. Past-month use of most drugs is up to seven
times higher among young people. However, cur-
rent use of “ecstasy” is nearly 20 times higher among
Differences in the extent of lifetime drug use should
be interpreted taking into account the “cohort
effect”, which pertains to differences in drug use,
related attitudes and behaviours among people born
during specific time periods.
3
Persons who reach
the age of greatest vulnerability to drug use initia-
tion during a period when drugs are popular and
widely available are at particularly high risk of trying
drugs and, possibly, continuing to use them.
4
One
such example in the United States of America is of
the “baby boomers” (those who were born between
1946 and 1964), who had the highest rates of sub-
stance use as young people compared with previous
cohorts.
5
Typically, when a cohort of people starts
using a certain substance in large numbers, as in the
case of baby boomers, this is reflected in lifetime
prevalence in the general population in the years to
come, even when many of them discontinue drug
use at a later stage. Therefore, lifetime prevalence is
an indicator of the extent of exposure of the popu-
lation and different age groups within the population
at any point in time to drugs, while past-year and
3 Lloyd D. Johnston and others, Monitoring the Future
National Survey Results on Drug Use: 2016 Overview, Key
Findings on Adolescent Drug Use (Ann Arbor, Michigan,
Institute for Social Research, University of Michigan,
2017).
4 J.D. Colliver and others, “Projecting drug use among aging
baby boomers in 2020”, Annals of Epidemiology, vol. 16,
No. 4 (April 2006), pp. 257–265.
5 J. Gfroerer and others, “Substance abuse treatment need
among older adults in 2020: the impact of the aging baby-
boom cohort”, Drug and Alcohol Dependence, vol. 69, No. 2
(March 2003), pp. 127–135.
Fig. 2
Prevalence of drug use in Europe, by age group, 2017
Source: EMCDDA.
Note: The information represented is the unweighted average of data from the European Union member States, Norway and Turkey,
reporting to EMCDDA on the basis of general population surveys conducted between 2012 and 2015.
0
5
10
15
20
25
30
Life-
time
Past
year
Past
month
Past
year
Past
month
Life-
time
Past
year
Past
month
15–24 years 25–34 years 45–54 years
Percentage
Cannabis
Cocaine
Amphetamines
"Ecstasy"
13
4
DRUGS AND AGE A. Drug use among young people and older people
people aged 15–24 than among those aged 45–54.
By contrast, the rates of lifetime prevalence of
cocaine in Europe among those aged 15–24 and
those aged 45–54 are comparable, while lifetime use
of cannabis is much higher among those aged under
35. This may reflect differences in the age of initia-
tion for those substances, as well as different
historical levels of use among young people in
Europe.
In England and Wales, the annual prevalence of
drug use was highest in the 20–24 age group for all
drug types in the period 2016–2017. For those aged
45 and older, the annual prevalence of drug use was
considerably lower.
Bolivia (Plurinational State of)
In the Plurinational State of Bolivia, recent and cur-
rent use of almost all substances is substantially
higher among those aged 18–24 than among those
in other age groups; as seen in the majority of coun-
tries, cannabis is the most commonly used drug
across most age groups. The lifetime use of cannabis,
cocaine, stimulants and inhalants is up to two times
higher among those aged 18–24 than those aged 36
or older. In most cases, the past-year and past-month
use of those substances is also reported at much
higher levels among those aged 18–24 than among
the 36–50 age group. For instance, the past-year use
of cannabis is more than six times higher among
those aged 18–24 than those aged 36–50.
Fig. 3
Annual prevalence of drug use in England and Wales, fiscal year 2016–17
Source: United Kingdom of Great Britain and Northern Ireland, Office for National Statistics, “Drug misuse: findings from the
2016/17 crime survey for England and Wales”, Statistical Bulletin 11/17 (London, July 2017).
Fig. 4
Prevalence of drug use in the Plurinational State of Bolivia, by drug type and age group, 2014
Source: Plurinational State of Bolivia, National Council against Drug Trafficking (CONALTID), II Estudio Nacional de Prevalencia y
Características del Consumo de Drogas en Hogares Bolivianos de Nueve Ciudades Capitales de Departamento, más la Ciudad de El
Alto, 2014 (La Paz, 2014).
0
2
4
6
8
10
12
14
16
18
General
population,
aged 16–59
years
16–19
years
20–24
years
25–29
years
30–34
years
35–44
years
45–54
years
55–59
years
Percentgae
Cannabis
Cocaine
"Ecstasy"
Hallucinogens
Amphetami nes
Ketamine
Mephe dr one
General
population,
aged 16–59
years
0
1
2
3
4
5
6
7
Life-
time
Past
year
Past
month
Life-
time
Past
year
Past
month
Life-
time
Past
year
Past
month
Life-
time
Past
year
Past
month
12–17 years 18–24 years 25–35 years 36–50 years
Percentage
Tranquillizers
Stimulants
Cannabis
Cocaine
Inhalants
14
WORLD DRUG REPORT 2018
among those aged 18–25 years is half of that among
those aged 50–54 years. This is probably the result
of a combination of factors, including the declining
trends in cocaine use that were observed in the
United States at the beginning of 2000 and the sharp
decline in such use that was observed in 2006. Con-
versely, the lifetime non-medical use of stimulants
and “ecstasy” among 18–25 year-olds is nearly three
times that of the older cohort, reflecting the more
recent appearance of these substances in the market.
The extent of past-month use of most drugs remains
up to three times higher and that of stimulants up
to seven times higher among those aged 18–25 than
among those aged 50–54. Hardly any current use
of “ecstasy” is reported among those 50 years and
older.
8
8 United States, Substance Abuse and Mental Health
Services Administration, Center for Behavioural Health
Statistics and Quality, Substance Abuse and Mental Health
Services Administration, Key Substance Use and Mental
Health Indicators in the United States: Results from the 2016
National Survey on Drug Use and Health”, HHS Publication
No. SMA 17-5044, NSDUH Series H-52 (Rockville,
Maryland, 2017).
Conversely, the lifetime and past-year non-medical
use of tranquillizers, the second-most misused sub-
stance in the Plurinational State of Bolivia, is almost
twice as high among those aged 36–50, although
the past-month use of tranquillizers was reported at
similar levels among all age groups, except for 12–17
year olds.
6
Kenya
In Kenya, older people report a higher use of estab-
lished substances such as khat in different forms
(miraa and muguka) and cannabis (bhang and hash-
ish), while drugs that have become available in Africa
more recently, such as cocaine and heroin, are
reported to be used more frequently among those
aged 18–24. Among the general population, khat
and cannabis remain the two most commonly used
substances, with the highest lifetime and past-year
use among those aged 25–35. Conversely, the life-
time use of cocaine, heroin and prescription drugs
is nearly three times higher among people aged
18–24 than among those aged 36 years and older.
United States
Data on drug use among the general population in
the United States from 2017 show differences in the
lifetime, past-year and past-month use of people
aged 18–25 years compared with that of people aged
50–54. These differences are partly explained by the
cohort effect. The cohort effect is visible in the life-
time prevalence of those who were young in the late
1960s and in the 1990s, which were times when an
increase occurred in the use of numerous drugs by
young people. Lifetime use of substances that have
an established use over decades, such as cannabis,
opioid painkillers, tranquillizers and inhalants, is
comparable among those aged 50–54 and those aged
18–25.
7
For example, almost half of people in both
age groups have used cannabis at least once in their
lifetime. This pattern is different for cocaine and
stimulants. The lifetime prevalence of cocaine
6 Plurinational State of Bolivia, National Council against
Drug Trafficking (CONALTID), II Estudio Nacional de
Prevalencia y Características del Consumo de Drogas en Hoga-
res Bolivianos de Nueve Ciudades Capitales ae Departamento,
más la Ciudad de El Alto, 2014 (La Paz, 2014).
7 United States, Substance Abuse and Mental Health Services
Administration, Center for Behavioural Health Statistics
and Quality, Results from the 2016 National Survey on Drug
Use and Health: Detailed Tables (Rockville, Maryland,
2017).
Fig. 5
Prevalence of drug use in Kenya, by
age group and drug type, 2012
Source: Kenya, National Authority for the Campaign Against
Alcohol and Drug Abuse, Rapid Situation Assessment of the
Status of Drug and Substance Abuse in Kenya (Nairobi, 2012).
0
2
4
6
8
10
12
Lifetime
Past yea r
Lifetime
Past yea r
Lifetime
Past yea r
Lifetime
Past yea r
15–17
years
18–24
years
25–35
years
36 years
and older
Percentage
Khat
Bhang
Cocaine
Heroin
Prescription drugs
DRUGS AND AGE B. Drugs and young people
15
4
Adolescence is the period when young people
undergo physical and psychological development
(including brain development); substance use may
affect that development. Adolescence is universally
a time of vulnerability to different influences when
adolescents initiate various behaviours, which may
include substance use. However, evidence shows
that the vast majority of young people do not use
drugs and those who do use them have been exposed
to different significant factors related to substance
use. The misconception that all young people are
equally vulnerable to substance use and harmful use
of substances ignores the scientific evidence, which
has consistently shown that individuals differ in
their susceptibility to use drugs. While specific influ-
ential factors vary between individuals, and no factor
alone is sufficient to lead to harmful use of sub-
stances, a critical combination of risk factors that
are present and protective factors that are absent
makes the difference between a young person’s brain
that is primed for substance use and one that is not.
Thus, from the perspective of preventing the initia-
tion of substance use, as well as preventing the
development of substance use disorders within the
context of the healthy and safe development of
young people, it is important to have a sound under-
standing of the patterns of substance use as well as
the personal social and environmental influences
that may result in substance use and substance use
disorders among young people.
B. DRUGS AND YOUNG
PEOPLE
Drugs affect young people in every part of the
world. Young people may use drugs, be involved
in the cultivation or production of drugs, or be
used as couriers. There are many factors at the
personal, micro (family, schools and peers) and
macro (socioeconomic and physical environment)
levels, the interplay of which may render young
people more vulnerable to substance use. Most
research suggests that early (12–14 years old) to
late (15–17 years old) adolescence is a critical risk
period for the initiation of substance use.
9
Many
young people use drugs to cope with the social and
psychological challenges that they may experience
during different phases of their development from
adolescence to young adulthood (ranging from the
need to feel good or simply to socialize, to personal
and social maladjustments).
10
9 United States, Substance Abuse and Mental Health Services
Administration, Center for Behavioral Health Statistics and
Quality. “Age of substance use initiation among treatment
admissions aged 18 to 30”, The TEDS Report, (Rockville,
Maryland, July 2014).
10 Jonathan Shedler and Jack Block, “Adolescent drug use
and psychological health: a longitudinal inquiry”, American
Psychologist, vol. 45, No. 5 (1990), pp. 612–630.
Fig. 6
Prevalence of drug use in the United States of America, by age group, 2017
Source: United States, Substance Abuse and Mental Health Services Administration, Center for Behavioural Health Statistics and
Quality, Results from the 2016 National Survey on Drug Use and Health: Detailed Tables (Rockville, Maryland, 2017).
For the purposes of the present section, as defined
by the United Nations, young people are considered
as those aged between 15 and 24 years.
0
10
20
30
40
50
60
Life-
time
Past
year
Past
month
Life-
time
Past
year
Past
month
Life-
time
Past
year
Past
month
12–17 years 18–25 years 50–54 years
Percentage
Cannabis
Cocaine
Methamphetamine
Misuse of pain relievers
Misuse of tranquillizers
Misuse of stimulants
Inhalants
"Ecstasy"
16
WORLD DRUG REPORT 2018
Patterns of drug use among
young people
Cannabis remains the most commonly
used drug
With the exception of tobacco and alcohol, cannabis
is considered the most commonly used drug among
young people. Epidemiological research, which is
mainly concentrated in high-income countries, sug-
gests that the perceived easy availability of cannabis,
coupled with perceptions of a low risk of harm,
makes cannabis, after tobacco and alcohol, the most
common substance used. Its use is typically initiated
in late adolescence and peaks in young adulthood.
11
Medical research shows that those who use cannabis
before the age of 16 face the risk of acute harm and
increased susceptibility to developing drug use dis-
orders and mental health disorders, including
personality disorders, anxiety and depression.
12, 13
Approximately 9 per cent of all people who experi-
ment with cannabis develop cannabis use disorders,
whereas 1 in 6 among those who initiate its use as
adolescents develop cannabis use disorders.
14
Between one quarter and one half of those who
smoke cannabis daily develop cannabis use
disorders.
15
The use of other drugs is typically preceded by can-
nabis use. When compared with non-users,
adolescent cannabis users have a higher likelihood
of using other drugs even when controlled for other
important co-variates such as genetics and environ-
mental influences.
16
Cannabis use during
adolescence and the subsequent use of other drugs
during young adulthood could be, among other
11 Megan Weier and others, “Cannabis use in 14 to 25 years
old Australians 1998 to 2013” Centre for Youth Substance
Abuse Research Monograph No. 1 (Brisbane, Australia,
Centre for Youth Substance Abuse, 2016).
12 Deidre M. Anglin and others, “Early cannabis use and
schizotypal personality disorder symptoms from adolescence
to middle adulthood”, Schizophrenia Research, vol. 137,
Nos. 1–3 (2012), pp. 45–49.
13 Shedler and Block “Adolescent drug use and psychological
health”.
14 Nora D. Volkow and others, “Adverse health effects of
marijuana use”, New England Journal of Medicine, 370(23)
(2014), pp. 2219–2227.
15 Ibid.
16 Jeffrey M. Lessem and others, “Relationship between
adolescent marijuana use and young adult illicit drug use”,
Behavior Genetics, vol. 36, No. 4 (2006), pp 498–506.
Cannabis use among
young people
In most countries, cannabis is the most widely used
drug, both among the general population and among
young people. A global estimate, produced for the
first time by UNODC, based on available data from
130 countries, suggests that, in 2016, 13.8 million
young people (mostly students) aged 15–16 years,
equivalent to 5.6 per cent of the population in that
age range, used cannabis at least once in the previ-
ous 12 months.
High prevalence of cannabis use was reported in North
America (18 per cent)
a
and in West and Central Europe
(20 per cent), two subregions in which past-year can-
nabis use among young people was higher than in
the general population in 2016. In some other sub-
regions, estimates suggest that cannabis use among
young people may be lower than among the general
population. More research is needed to understand
whether such a difference reflects the initiation of
cannabis use at a later age in the areas concerned or
is the result of comparatively higher under-reporting
of drug use behaviour in young people due to sigma.
Another factor may be that, at the age of 15–16, not
all young people are necessarily still at school in some
developing countries. Those in that age group who
are still at school may not be representative of their
age range regarding drug use behaviour; they may be
part of an elite exhibiting lower drug use than those
who are no longer at school.
a
Excluding Mexico: 23 per cent.
Annual prevalence of cannabis use among
the general population aged 15–64 years
and among students aged 15–16 years,
2016
Sources: UNODC, annual report questionnaire data and
government reports.
Note: the estimate of past-year cannabis use in young
people aged 15–16 years is based on school surveys in most
countries, hence the use of the term “students”.
11.0
8.0
7.6
5.1
1.9
11.4
11.6
6.6
13.9
2.7
0
2
4
6
8
10
12
14
16
Oceania Americas Africa Europe Asia
Annual prevalence (percentage)
General population (aged 15-64 years)
Students (aged 15-16 years)
General population (aged 15–64 years)
Students (aged 15–16 years)
Percentage
DRUGS AND AGE B. Drugs and young people
17
4
of drugs such as cocaine, tranquillizers, LSD and
inhalants was also reported among students in all
four countries. The proportion of those who initi-
ated drug use at a young age varied among males
and females in the survey, with the extent of drug
use among male students twice as high as among
female students. Polydrug use was also common
among the students, with one third of the students
in Colombia reported having used two or more
drugs concurrently in the past year, compared with
20 per cent in Ecuador and 7 per cent in Peru. Can-
nabis, cocaine, LSD and ecstasy were among the
substances most commonly reported as used
concurrently.
Spectrum of drug use in young people:
from nightlife settings to the use of
inhalants among street children
There are two contrasting settings that illustrate the
wide range of circumstances that drive drug use
among young people. On the one hand, drugs are
used in recreational settings to add excitement and
enhance the experience; on the other hand, young
people living in extreme conditions use drugs to
cope with the difficult circumstances in which they
find themselves. This section briefly describes drug
use among young people in those settings.
Use of stimulants in nightlife and
recreational settings
Over the past two decades, the use among young
people in high-income countries and those in urban
reasons, the result of common and shared environ-
mental factors. Adolescent users of cannabis may
come into contact with other cannabis-using peers
or drug dealers who supply other drugs, which may
result in increased exposure to a social context that
encourages the use of other drugs.
17, 18
For example,
a longitudinal study among adolescent twins showed
that the twin who used cannabis differentially pro-
gressed towards the use of other drugs, alcohol
dependence and drug use disorders at rates that were
twice or even five times higher than the twin who
did not use cannabis.
19
A comparative study of drug use among university
students (18–25 and older) in Bolivia (Plurinational
State of), Colombia, Ecuador and Peru in 2016
showed that, after alcohol and tobacco, cannabis
was the most commonly used drug among univer-
sity students. Some 20 per cent of the students in
Colombia had used cannabis in the past year, com-
pared with 5 per cent in Bolivia (Plurinational State
of) and Peru.
The reported use of other substances was also high-
est among university students in Colombia. The use
17 Ibid.
18 Wayne D. Hall and Michael Lynskey, “Is cannabis a
gateway drug? Testing hypotheses about the relationship
between cannabis use and the use of other illicit drugs”,
Drug and Alcohol Review, vol. 24, No. 1 (2005), pp. 39–
48.
19 Lessem and others, “Relationship between adolescent
marijuana use and young adult illicit drug use”.
Fig. 7
Prevalence of drug use among university students in Bolivia (Plurinational State of),
Colombia, Ecuador and Peru, 2016
Source: UNODC, III Estudio Epidemiológico Andino sobre Consumo de Drogas en la Población Universitaria: Informe Regional
2016 (Lima, 2017).
* Includes amphetamine, methamphetamine and "ecstasy".
0
1
2
3
4
5
6
7
8
9
10
Life-
time
Past
year
Past
month
Life-
time
Past
year
Past
month
Life-
time
Past
year
Past
month
Life-
time
Past
year
Past
month
Bolivia
(Plurnational State of)
Colombia Ecuador Peru
Percentage
Cocaine
LSD
Ampahetamine-type stimulants*
Tranquillizers
Inhalants
Bolivia Colombia Ecuador Peru
(Plurnational State of)
18
WORLD DRUG REPORT 2018
centres of club drugs such as MDMA, or “ecstasy”,
methamphetamine, cocaine, ketamine, LSD and
GHB, has spread from isolated rave scenes to set-
tings ranging from college bars and house parties to
concerts. Some evidence on the approaches of young
people to these drugs has been collected in specific
contexts.
A qualitative study of club drug users in New York
City, for example, found that club drug use could
be grouped into three main patterns.
20
The first
group were inclined to use mainly cocaine, but infre-
quently, and were identified as “primary cocaine
users”. This group had no exposure to other drugs
or were disinclined to use multiple substances. The
second group were identified as “mainstream users”;
they were more inclined to experiment but were
focused on the most popular club drugs. This group
had a higher frequency of use and were also likely
to have used “ecstasy”, but were not likely to have
extensive experience with other club drugs. The
third group were identified as “wide-range users”;
they had a higher frequency of use of more than one
drug and were willing to experience “getting high”
in different ways. Although there is heterogeneity
among the third group, their drug use behaviours
have been associated with profound immediate and
long-term consequences.
Use of stimulants among socially integrated
and marginalized young people
Outside nightlife settings, stimulants such as meth-
amphetamine are also quite commonly used among
young people in most parts of the world. A qualita-
tive study in the Islamic Republic of Iran, identified
three groups of young methamphetamine users.
21
The majority were those who had started using
methamphetamine, known locally as shisheh, as a
way of coping with their current opioid use, either
to self-treat opioid dependence or to manage its
adverse events. Another, smaller group, were those
who had used shisheh during their first substance
20 Danielle E. Ramo and others, “Typology of club drug use
among young adults recruited using time-space sampling”,
Drug and Alcohol Dependence, vol. 107, Nos. 2 and 3
(2010), pp. 119–127.
21 Alireza Noroozi, Mohsen Malekinejad and Afarin Rahimi-
Movaghar, “Factors influencing transition to shisheh
(methamphetamine) among young people who use drugs
in Tehran: a qualitative study”, Journal of Psychoactive Drugs
(29 January 2018).
use or after a period of cannabis use, as novelty-
seeking and to experience a new “high”. The last
group constituted those who had switched to meth-
amphetamine use after participating in an opioid
withdrawal programme and abstaining from opioid
use for a period of time.
A review of studies in Asia and North America of
risk factors among young people using metham-
phetamine identified a range of factors associated
with methamphetamine use among socially inte-
grated (low-risk) and marginalized (high-risk)
groups of users.
22
Among socially integrated young
people, males were more likely than females to use
methamphetamine. Among that group, a history of
engaging in a variety of risky behaviours, including
sexual activity under the influence and concurrent
alcohol and opiate use, was significantly associated
with methamphetamine use. Sexual lifestyle and
risky sexual behaviour were also considered risk fac-
tors. Engaging in high-risk sexual behaviour,
however, could be a gateway for methamphetamine
use, or vice versa. Among marginalized groups,
females were more likely than males to use meth-
amphetamines. Young people who had grown up
in an unstable family environment or who had a
history of psychiatric disorders were also identified
as being at a higher risk of methamphetamine use.
Drug use among street children
While street children or street-involved youth are a
global phenomenon, the dynamics that drive chil-
dren to the streets vary considerably between
high-income and middle- and low-income coun-
tries.
23
Young people in this situation in high-income
countries have typically experienced conflict in the
family, child abuse and/or neglect, parental sub-
stance use or poverty. In resource-constrained
settings in low and middle-income countries, young
people may be on the street because of abject pov-
erty, the death of one or both parents or displacement
as a result of war and conflict in addition to the
reasons cited above.
22 Kelly Russel and others, “Risk factors for methamphetamine
use in youth: a systematic review”, BioMed Central
Pediatrics, vol. 8, No. 48 (2008).
23 Lonnie Embleton and others, “The epidemiology of
substance use among street children in resource-constrained
settings: a systematic review and meta-analysis”, Addiction,
vol. 108, No. 10 (2013), pp. 1722–1733.
DRUGS AND AGE B. Drugs and young people
19
4
physical abuse of street children is strongly associ-
ated with their sexual and physical victimization.
25,
26
These vulnerabilities, together with the fact that
street children may have families or parents with
substance use problems, contribute to the develop-
ment of substance use and psychiatric disorders
among street children.
High levels of substance use among street children
have been observed in many studies, but there are
no global estimates and their patterns of substance
25 Kimberly A. Tyler and Lisa A. Melnder, “Child abuse,
street victimization and substance use among homeless
young adults”, Youth and Society, vol. 47, No. 4 (2015), pp.
502–519.
26 Khaled H. Nada and El Daw A. Suliman, “Violence, abuse,
alcohol and drug use, and sexual behaviors in street children
of Greater Cairo and Alexandria, Egypt”, AIDS, vol. 24,
Suppl. 2 (2010), pp. S39–S44.
Not only do street children live, survive and grow
in an unprotected environment, but they also might
be abused or exploited by local gangs or criminal
groups to engage in street crimes or sex work. To
survive in such a hostile environment, street children
may do odd jobs such as street vending, hustling,
drug dealing or begging, or may engage in “survival
sex work”, which is the exchange of sex for specific
food items, shelter, money or drugs. Living in pre-
carious conditions also makes street children and
youth vulnerable to physical abuse, injuries and vio-
lence perpetuated by criminals, gangs or even local
authorities.
24
It has also been shown that sexual and
24 WHO, “Working with street children: module 1, a pro-
file of street children – a training package on substance
use, sexual and reproductive health including HIV/AIDS
and STDs”, publication No. WHO/MSD/MDP/00.14
(Geneva, 2000).
Table 1
Lifetime prevalence of different substances among street-involved children and youth in
resource-constrained settings
Source: Lonnie Embleton and others, “The epidemiology of substance use among street children in resource-constrained settings:
a systematic review and meta-analysis”, Addiction, vol. 108, No. 10 (2013), pp. 1722–1733.
a
Pooled analysis is a statistical technique for combining the results, in this case the prevalence from multiple epidemiological studies, to
come up with an overall estimate of the prevalence.
Substance used
Pooled analysis
a
of lifetime
prevalence (percentage)
Confidence interval
Alcohol 41 31–50
Tobacco 44 34–55
Cannabis 31 18–44
Cocaine 7 5–9
Inhalants 47 36–58
Children working and living on the streets: street-involved children
UNICEF defines street children or youth as any girl or boy
who has not reached adulthood, for whom the street
has become her or his habitual abode and/or source of
livelihood, and who is inadequately protected, supervised
or directed by responsible adults.
Street children are categorized by their level of involve-
ment in the streets into the following three groups:
1. Child of the streets: has no home but the streets.
The child may have been abandoned by their fam-
ily or may have no family members left alive. Such
a child has to struggle for survival and might move
from friend to friend, or live in shelters such as
abandoned buildings.
2. Child on the street: visits his or her family regu-
larly. The child might even return every night to
sleep at home but spends most days and some
nights on the street because of poverty, over-
crowding or sexual or physical abuse at home.
3. Child part of a street family: some children live
on the streets with the rest of their families, who
may have been displaced because of poverty, natu-
ral disasters or wars. They move their possessions
from place to place when necessary. Often, the
children in these families work on the streets with
other members of their families.
Source: WHO, “Working with street children: module 1, a
profile of street children – a training package on substance
use, sexual and reproductive health including HIV/AIDS
and STDs”, publication No. WHO/MSD/MDP/00.14
(Geneva, 2000).
20
WORLD DRUG REPORT 2018
interviewed for a study in Kenya reported using glue
in the past month, making it the most commonly
used substance among this group.
31
Other sub-
stances used by the children included alcohol,
tobacco, miraa (a local psychoactive herb), cannabis
and petrol. There were considerable differences in
the extent of substance use among different catego-
ries of street children. The prevalence of past-month
use was 77 per cent among those categorized as
“children of the street”, compared with 23 per cent
reported by “children on the street” (see box for the
definition.) Being male, older and having been on
the streets for a longer period of time has also been
associated with substance use.
32, 33
Similarly, the
absence of family has been consistently associated
with substance use among street-involved youth.
34
The use of psychoactive substances among street-
involved children and youth is often part of their
coping mechanism in the face of adverse experiences,
such as the physical and sexual abuse and exploitation
they experience being on the streets.
35
Therefore,
many street-involved children perceive inhalants as
a form of comfort and relief in a harsh environment,
as they numb feelings. In one study, “wanting to
forget or escape problems” was reported as the main
reason for substance use among street-involved
children. For many, peer pressure and the nature of
their jobs influenced their use of inhalants.
36
31 Lonnie Embleton and others, “Knowledge, attitudes, and
substance use practices among street children in western
Kenya”, Substance Use and Misuse, vol. 47, No. 11 (2012),
pp. 1234–1247.
32 Embleton and others, “The epidemiology of substance use
among street children in resource-constrained settings”.
33 Yone G. de Moura and others, “Drug use among street
children and adolescents: what helps?”, Cadernos Saúde
Pública, vol. 28, No. 6 (2012), pp. 1371–1380.
34 Embleton and others, “The epidemiology of substance use
among street children in resource-constrained settings”.
35 UNODC, Solvent Abuse among Street Children in Pakistan,
Publication No. UN-PAK/UNODC/2004/1 (Islamabad,
2004).
36 A. Elkoussi and S. Bakheet, “Volatile substance misuse
among street children in Upper Egypt”, Substance Use and
use may vary considerably. A systematic review and
meta-analysis of studies on substance use among
street children in resource-constrained settings
reported that inhalants were the most common sub-
stance used, with a pooled analysis
27
putting lifetime
prevalence of their use among street-involved chil-
dren and youth at 47 per cent.
28
While the use of
inhalants was found in all regions, use of cocaine
among street-involved children was reported mainly
in South and Central America, and alcohol use
mostly in Africa and South and Central America.
Most of the scientific literature on the subject reports
the use of inhalants or volatile substances among
street children as a common phenomenon.
29
Such
substances include paint thinner, petrol, paint, cor-
rection fluid and glue. They are selected for their
low price, legal and widespread availability and abil-
ity to rapidly induce a sense of euphoria among
users.
30
There are also differences in the extent of substance
use among street children that depend on the dura-
tion of their exposure to the street environment.
Some 58 per cent of street-involved children
27 A pooled analysis is a statistical technique for combining
the results, in this case the prevalence from multiple
epidemiological studies, to arrive at an overall estimate of
the prevalence.
28 Embleton and others, “The epidemiology of substance use
among street children in resource-constrained settings”. The
meta-analysis looked at 50 studies on substance use among
street children. Out of 27 studies, 13 covered resource-
constrained settings in Africa, South and Central America,
Asia, including the Middle East, and Eastern Europe.
29 L. Baydala, “Inhalant abuse”, Paediatrics Child Health, vol.
15, No. 7 (September 2010), pp. 443–448.
30 Colleen A. Dell, Steven W. Gust and Sarah MacLean,
“Global issues in volatile substance misuse”, Substance Use
and Misuse, vol. 46, Suppl. No. 1 (2011), pp. 1–7.
Different ways of using
inhalants
Sniffing: solvents are inhaled directly from a con-
tainer through the nose and mouth.
Huffing: a shirt sleeve, sock or a roll of cotton
is soaked in a solvent and placed over the nose
or mouth or directly into the mouth to inhale the
fumes.
Bagging: a concentration of fumes from a bag is
placed over the mouth and nose or over the head.
Sudden sniffing death
The intensive use of volatile substances (even during
only one session) may result in irregular heart
rhythms and death within minutes, a syndrome
known as “sudden sniffing death”.
DRUGS AND AGE B. Drugs and young people
21
4
and more than half of adolescent street-involved
girls had received payment for sex or had been forced
to have sex.
41
The above-mentioned study in Paki-
stan showed that slightly more than half of street
children had exchanged sex for food, shelter, drugs
or money.
Street-involved children remain one of the most
vulnerable, marginalized and stigmatized groups.
They are exposed to abuse and violence, drug use
and other behaviours that put them at high risk of
HIV and tuberculosis infection, and other condi-
tions including malnutrition and general poor
health. Despite these vulnerabilities, they are often
the most likely to be excluded from receiving any
form of social or health-care support to ameliorate
their condition.
42
Polydrug use remains common among
young people
As with adults, a major characteristic of drug use
among young people is the concurrent use of more
than one substance. Polydrug use remains fairly
common among both recreational and regular drug
users. However, polydrug use among young adults
is symptomatic of more established patterns of use
of multiple substances, which is linked to an
increased risk of developing long-term problems as
well as of engaging in acute risk-taking through
binge drinking or binge use of stimulants such as
“ecstasy” at rave parties or similar settings.
43
Evidence collected in some regions and countries
shows examples of the level and combinations of
substances typically used by young people. In
Europe, a wide variation in patterns of polydrug use
among the population of drug users was reported,
ranging from occasional alcohol and cannabis use
to the daily use of combinations of heroin, cocaine,
alcohol and benzodiazepines.
44
The most common
polydrug use combinations reported in Europe
41 Busza and others, “Street-based adolescents at high risk of
HIV in Ukraine”.
42 UNICEF, The State of the World’s Children 2012: Children
in an Urban World (United Nations publication, Sales No.
E.12.XX.1).
43 EMCDDA, Polydrug Use: Patterns and Response (Luxem-
bourg, Office for Official Publications of the European
Communities, 2009).
44 Ibid.
The injecting of drugs is also reported among street-
involved youth. A cross-sectional study in Ukraine
reported that 15 per cent of the children living on
the streets were injecting drugs. Nearly half of them
shared injecting equipment and 75 per cent were
sexually active.
37
In another study among street
children in Pakistan, cannabis and glue were the
drugs most commonly used by the respondents (80
per cent and 73 per cent, respectively), while 9 per
cent smoked or sniffed heroin and 4 per cent
injected it.
38
Similarly, in a Canadian prospective
cohort study among street-involved youth, 43 per
cent of participants reported injecting drugs at some
point.
39
Moreover, being helped with injecting was
seen among a more vulnerable subgroup of
respondents, i.e., those who were young and/or
female. Those respondents were more likely to
receive help in injecting methamphetamine than
heroin or cocaine, in particular because of the higher
daily frequency of injecting reported for
methamphetamine.
Sexual abuse and exploitation is a common feature
in the lives of street-involved children and may con-
tribute to substance use. A study in Brazil reported
that a significantly higher proportion of street-
involved boys (two thirds) as compared with girls
(one third) reported having had sex at some point
in their lives. Over half of the respondents reported
becoming sexually active before the age of 12.
Almost half of the street-involved children inter-
viewed reported more than three sexual partners in
the past year. One third of the children reported
having had unprotected sex under the influence of
drugs or alcohol.
40
In Ukraine, a study showed that
nearly 17 per cent of street-involved adolescent boys
Misuse, vol. 46, Suppl. No. 1 (2011), pp. 35–39.
37 Joanna R. Busza and others, “Street-based adolescents at
high risk of HIV in Ukraine”, Journal of Epidemiology and
Community Health, vol. 65, No. 11 (2011), pp. 1166–1170.
38 Susan S. Sherman and others, “Drug use, street survival,
and risk behaviours among street children in Lahore,
Pakistan”, Journal of Urban Health, vol. 82, Suppl. No. 4
(2005), pp. iv113–iv124.
39 Tessa Cheng and others, “High prevalence of assisted
injection among street-involved youth in a Canadian
setting”, AIDS and Behaviour, vol. 20, No. 2 (20160, pp.
377–384.
40 Fernanda T. de Carvalho and others, “Sexual and drug
use risk behaviours among children and youth in street
circumstances in Porto Alegre, Brazil”, AIDS and Behaviour,
vol. 10, Suppl. No. 1 (2006), pp. 57–66.
22
WORLD DRUG REPORT 2018
Pathways to substance use disorders
Integrative developmental model for
understanding pathways to substance
use and harmful use of substances
Persons who initiate substance use and later develop
substance use disorders typically transition through
a number of stages, including initiation of use, esca-
lation of use, maintenance, and, eventually,
addiction.
48, 49
These pathways fluctuate in the use
and desistance or cessation of drug use. Some groups
of users may maintain moderate use for decades and
never escalate. Others may exhibit intermittent peri-
ods of cessation, abstain permanently, or escalate
rapidly and develop substance use disorders.
Understanding the risk factors that determine
whether experimental users continue on a path to
harmful use of substances is a question that has com-
pelled researchers and practitioners to try to better
understand, predict and appropriately intervene in
these distinct etiological pathways.
The “ecobiodevelopmental” theoretical framework,
founded on an integration of behavioural science
fields, can help elucidate substance use pathways.
In this model, human behaviour is viewed as the
result of emerging from the “biological embedding”
50
48 On the basis of the International Statistical Classification
of Diseases and Related Health Problems (ICD 10)
definition, the term “harmful use of substances” has been
used in the present section instead of the term “substance
abuse” to refer to a pattern of use that causes damage to
physical or mental health. The Diagnostic and Statistical
Manual of Mental Disorders (DSM-5) of the American
Psychiatric Association refers to “substance use disorder”
as patterns of symptoms resulting from the use of a
substance despite experiencing problems as a result of
using substances. Depending on the number of symptoms
identified, substance use disorder may vary from moderate
to severe. Many of the scientific literature that dates prior
to the introduction of DSM-5 refers to “substance abuse”,
which was defined in DSM-4 as a maladaptive pattern of
substance use leading to clinically significant impairment
or distress, including recurrent substance use in which it
is hazardous or continuous use despite persistent social
or interpersonal problems. Similarly, the term “addiction”
refers to a chronic relapse condition that is characterized by
compulsive drug-seeking despite harmful consequences.
49 Denise B. Kandel, ed., Stages and Pathways of Drug
Involvement: Examining the Gateway Hypothesis (Cambridge,
Cambridge University Press, 2002).
50 “Biological embedding” refers to how early personal
experiences and environmental exposure are “built into the
bodies”.
included tobacco, alcohol and cannabis, together
with “ecstasy”, cocaine, amphetamines, LSD or
heroin.
In a national survey among college students in
Brazil, cannabis, amphetamines, inhalants, tranquil-
lizers and hallucinogens were the five drugs most
frequently used with alcohol both in the past 12
months and in the past 30 days.
45
The results of the
National Survey on Drug Use and Health in the
United States showed that polydrug use among cur-
rent “ecstasy” users aged 18–29 years was a common
feature: among those users, 44 per cent had used
three or more types of drug in the past year.
46
The
most common combinations included cannabis,
cocaine, tranquillizers and opiates.
The use of heroin and other opioids is problematic
not only because of the potential for developing
opioid use disorders, but also because of the
increased likelihood of developing health problems
associated with unsafe injecting practices. In the
past decade, heroin use among young people showed
declining trends in North America, but a recent
resurgence of opioid use, along with the risky use
of multiple substances, is also affecting young
people. A qualitative study of young people who
injected heroin in the United States showed that
misuse of prescription opioids and tranquillizers was
also quite common among them. They misused
tranquillizers and prescription opioids not only as
a substitute for heroin, but also to boost the effects
of heroin, to manage withdrawals or even to reduce
use or the risks associated with injecting heroin.
47
45 Lúcio G. de Oliveria and others, “Polydrug use among
college students in Brazil: a nationwide survey”, Revista
Brasileira de Psiquiatria, vol. 35, No. 3 (2013), pp. 221–
230.
46 Katherine M. Keyes, Silvia S. Martins and Deborah S.
Hasin, “Past 12-month and lifetime comorbidity and
poly-drug use of ecstasy users among young adults in the
United States: results from the national epidemiologic
survey on alcohol and related conditions”, Drug and Alcohol
Dependence, vol. 97, Nos. 1 and 2 (2008), pp. 139–149.
47 E. S. Lankenau and others, “Patterns of prescription drug
misuse among young injection drug users”, Journal of
Urban Health, vol. 89, No. 6 (December 2012).
DRUGS AND AGE B. Drugs and young people
23
4
of social and physical environmental conditions.
51
Individual-level characteristics, such as personality
and genetics, interact with experiences and exposures
to socioenvironmental factors to directly affect the
developing brain’s structure and function.
52, 53, 54
This inherent “experience-dependence” of the brain
means that the nature of conditions to which indi-
viduals are exposed — both optimal and suboptimal
— influence the resultant behaviour. An abundance
of positive experiences, such as protective factors
including family support or well-equipped schools,
can strengthen the neural connections underlying
51 Jack P. Shonkoff and Deborah A. Phillips, eds., From
Neurons to Neighborhoods: The Science of Early Childhood
Development (Washington, D. C., National Academy Press,
2000).
52 Hirokazu Yoshikawa, Lawrence J. Aber and William R.
Beardslee, “The effects of poverty on the mental, emotional,
and behavioral health of children and youth: Implications
for prevention”, American Psychologist, vol. 67, No. 4
92012), pp. 272–284.
53 Megan M. Sweeney, “Family-structure instability and ado-
lescent educational outcomes: a focus on families with step-
fathers”, in Whither Opportunity? Rising Inequality, Schools,
and Children’s Life Chances, Greg J. Duncan and Richard J.
Murnane, eds. (New York, Russell Sage Foundation, 2011),
pp. 229–252.
54 Mary E. O’Connell, Thomas Boat and Kenneth E. Warner,
eds., Preventing Mental, Emotional, and Behavioral Disorders
among Young People: Progress and Possibilities. (Washington,
D. C., National Academies Press, 2009).
self-regulation, impulse control and executive deci-
sion-making. On the other hand, negative or adverse
exposures can translate into impairments in a devel-
oping child’s ability to regulate behaviour and
emotions.
55, 56
Therefore, the exposures and experi-
ences during an individual’s developmental stage
have differential effects on social, psychological and
neural processes and have functional and behav-
ioural implications.
57, 58
Immediate micro-level factors, such as the family,
and surrounding macro-level factors, such as the
neighbourhood, which influence the development
and prevalence of behaviour on individual function-
ing, are acknowledged in this framework.
While specific influential factors vary between indi-
viduals, and no factor alone is sufficient to lead to
55 Danya Glaser, “Child abuse and neglect and the brain: a
review”, Journal of Child Psychology and Psychiatry, vol. 41,
No. 1 (2000), pp. 97–116.
56 Bruce S. McEwen and John H. Morrison, “The brain on
stress: vulnerability and plasticity of the prefrontal cortex
over the life course”, Neuron, vol. 79, No. 1 (2013), pp.
16–29.
57 Susan L. Andersen, “Commentary on the special issue
on the adolescent brain: adolescence, trajectories, and the
importance of prevention”, Neuroscience and Biobehavioral
Review, vol. 70 (2016), pp. 329–333.
58 Sara B. Johnson, Jenna L. Riis and Kimberly G. Noble,
“State of the art review: poverty and the developing brain”,
Pediatrics, vol. 137, No. 4 (2016).
Fig. 8
Factors that determine different pathways to substance use and substances use disorders
Figure 8 shows the two main categories of factors conferring risk for substance use: genes and the environment. Genetic variants are like
switches: they are either turned on or off, but their expression is influenced by experience (i.e., epigenetic modifications). Environmental fac-
tors are more like dials that are turned up or down, also depending on experience. Risk or adversity factors include child maltreatment, pov-
erty, poorly equipped schools, dysfunctional families, discrimination and witnessing violence. Resiliency or protective factors include
high-quality education, housing, health care, social attachments and parenting. The combination of switches and dials crosses a liability
threshold that, when predominantly negative, primes the brain for substance use. The functional relationship between factors is not linear,
nor is it static; it fluctuates throughout a lifespan. Some environmental influences confer resiliency and may attenuate the effects of genetic
predispositions. Thus, psychosocial interventions and practices are of the utmost importance in determining final outcomes.
G
e
n
e
t
i
c
p
r
e
d
i
s
p
o
s
i
t
i
o
n
E
p
i
g
e
n
e
t
i
c
m
o
d
i
f
i
c
a
t
i
o
n
s
E
n
v
i
r
o
n
m
e
n
t
a
l
f
a
c
t
o
r
s
I
n
t
e
r
m
e
d
i
a
t
e
p
h
e
n
o
t
y
p
e
Brain structure
and function
Adversity
Resilience
Liability/Risk
Threshold for
drug use
disorders
Pathways to substance use
Behaviour
modifications
• Self-regulation
• Mood stability
• Novelty seeking
• Impulsivity
Initiation
of use
24
WORLD DRUG REPORT 2018
unique to each individual and can be affected by
any number of potential combinations of external
and personal factors. Brain development is exqui-
sitely sensitive to psychosocial experiences. Such
experiences affect the way the brain develops and
functions and have a direct impact on a child’s abil-
ity to self-regulate and, ultimately, on susceptibility
to substance use. Substance use among adolescents
is of particular concern given the evidence that sub-
stances with psychoactive effects have a greater
impact on adolescents than adults. Age-related vari-
ations in drug responses are likely the result of
differences in the pharmacological effects of sub-
stances on the brain systems that are still under
construction. These differences may have significant
implications for adolescents increasing the tendency
to consume greater amounts and more drug types,
thereby, compromising their neurodevelopment.
harmful use of substances, there may be some criti-
cal combination of risk factors that are present and
protective factors that are absent that makes the
difference between having a brain that is primed for
substance use and one that is not. This threshold is
The evolution and the impact of
drug use in childhood and youth
can be characterized by three
elements:
• Risk factors that determine the fragility or
resilience of the individual to drug dependence
• The health and social impact of drug use on
individual development
• The impact of caregivers’ drug use on the
individual
Substance use and
related problems
•
Academic failure
•
Poor social competency
skills
•
•
Mental health problems
•
Poor physical health
PRIMARY
OUTCOME
PERSONAL
CHARACTERISTICS
Genec suscepbilies
Mental health and
personality traits
•
•
Agressive
•
•
Impulsive
•
Mental health problems
Neurological development
•
Language delays
•
•
Poor decision making and
problem solving
Stress reacvity
•
•
Dysregulated physiological
responses
•
Poor coping
Family influences
•
Lack of involvement and
monitoring
•
•
•
Neglect for physical
•
environment
•
Parental substance use
School influences
•
•
•
•
•
Peer influence
•
role models
•
Exposure to alcohol,
tobacco, other drug use,
violence, crime
•
Lack of parental monitoring
•
Social networking
technology
INFLUENCES
Income and resources
•
Poverty
•
Homeless, refugee status
•
Child labour
•
Lack of access to health care
Social environment
•
informal social controls
•
Lack of social cohesion,
disconnectedness,
lack of social capital
•
•
Social exclusion, inequality,
Physical environment
•
Decay: abandoned
buildings, substandard
housing
•
Neighborhood disorder
•
Access to alcohol, tobacco,
•
Lack of access
foods
•
Exposure to toxics
•
Media
INFLUENCES
Fig. 9
Risk factors in substance use and harmful use of substances
Research has identified these environmental influences as key in
determining ultimate behavioural outcomes. They do not act
alone, however; they interact with personal characteristics to
alter pathways to substance use and harmful use. Thus, it is
important that prevention strategies take into account these
complex interactions to identify relevant targets for programmes
and policies in any given individual, community or population.
DRUGS AND AGE B. Drugs and young people
25
4
heightened reward sensitivity, poor inhibitory
control, aggression and novelty-seeking.
60, 61
Variation in these personality dimensions,
particularly impulsivity and novelty-seeking, may
contribute to the initiation of substance use, as well
as the transition from initial to intermittent and
then regular substance use, the transition from
harmful use to dependence or addiction, and the
propensity for repeated relapse after achieving
abstinence.
62
Individuals with these traits tend to
seek highly stimulating and risky situations and
show less anxiety in anticipation of the consequences
of their behaviour.
63, 64
Similar to environmental factors, personality influ-
ences also have a differential impact on these
complex behaviours at different stages of an indi-
vidual’s development.
65, 66
Normative development
during adolescence is typified by heightened levels
of impulsivity and novelty-seeking, in part due to
dramatic fluctuations in hormone levels that affect
brain development and other systems. The subgroup
of adolescents that exhibits an especially high level
of any combination of these personality traits is at
heightened risk of harmful use of substances. These
characteristics may, in effect, contribute to indi-
vidual differences in the reinforcing effects of
drugs.
67
60 Michael J. Frank and others, “Genetic triple dissociation
reveals multiple roles for dopamine in reinforcement
learning”, Proceedings of the National Academy of Sciences,
vol. 104, No. 41 (2007), pp. 16311–16316.
61 Tilmann A. Klein and others, “Genetically determined
differences in learning from errors”. Science, vol. 318, No.
5856 (2007), pp. 1642–1645.
62 Mary J. Kreek and others, “Genetic influences on
impulsivity, risk taking, stress responsivity and vulnerability
to drug abuse and addiction”, Nature Neuroscience, vol. 8,
No. 11 (2005), pp. 1450–1457.
63 Ibid.
64 Didier Jutras-Aswad and others, “Cannabis-dependence risk
relates to synergism between neuroticism and proenkephalin
SNPs associated with amygdala gene expression: case-
control study” PloS ONE, vol. 7, No. 6 (2012).
65 James J. Li and others, “Polygenic risk, personality
dimensions, and adolescent alcohol use problems: a
longitudinal study”, Journal of Studies on Alcohol and Drugs,
vol. 78, No. 3 (2017), pp. 442–451.
66 Kenneth S. Kendler, Charles O. Gardner and Carol A.
Prescott, “Personality and the experience of environmental
adversity”, Psychological Medicine, vol. 33, No.7 (2003), pp.
1193–1202.
67 Caryn Lerman and Raymond Niaura, “Applying genetic
Risk and protective factors
The present subsection contains a discussion of the
association of person-level micro- and macro-level
risk factors in substance use and harmful use as
sources of vulnerability versus resilience. The
consequences of eventual substance use for child
and adolescent development and the multiple
impacts of caregiver substance use on the
development of the child and adolescent are also
discussed. Throughout the subsection, the evidence
of aetiology (causation) and knowledge regarding
the consequences of drug use for the child and
adolescent are discussed within the context of an
integrated developmental framework.
Individual-level risk factors
An individual’s characteristics play a significant role
in determining whether that individual will use sub-
stances, will progress to harmful use of substances
or will develop substance use disorders, or whether
the individual will abstain from or desist such use
during the developmental pathway. Taking these
characteristics into account is important for three
reasons: (a) neurobiological functioning, personal-
ity, emerging stress and coping strategies help to
determine an individual’s response to prevailing
social and environmental influences, contributing
to eventual outcomes; (b) personal-level character-
istics have been shown to predict or moderate
outcomes, as they interact with environmental influ-
ences in unique and complex ways; and (c) knowing
these characteristics is critical in determining what
prevention and treatment interventions may have
the greatest potential to benefit any given individual
or subgroup. This information can also help identify
opportunities during the development of an indi-
vidual for implementing the most effective
prevention strategies. Favourable changes in these
characteristics are expected if the intervention posi-
tively influences its targets (a mediation effect).
Particular personality traits have been associated
with externalizing disorders, which have been
consistently implicated in the use and harmful use
of substances.
59
These characteristics include
59 Irene J. Elkins, Matt McGue and William G. Iacono,
“Prospective effects of attention-deficit/hyperactivity
disorder, conduct disorder, and sex on adolescent substance
use and abuse”, Archives of General Psychiatry, vol. 64, No.
10 (2007), pp. 1145–1152.
26
WORLD DRUG REPORT 2018
hyperactivity disorder effectively meeting social chal-
lenges is diminished, as doing so requires intact
neurocognitive and emotional functions which are
often compromised in psychiatric disorders.
73
Some of the mental health conditions that may be
correlated with drug use have a gender factor, which
translates into a gender differential in terms of the
risk of harmful use and drug dependence: males
more often exhibit antisocial personality disorder,
while females demonstrate higher rates of mood and
anxiety disorders.
74
Among both adolescents and
adults, efforts to self-manage psychiatric symptoms
further compound the harmful use of substances,
as well as adding to the challenges associated with
resistance to treatment for substance use disorders.
75
Neurological development and adolescence
One pathway to harmful use of substances is believed
to originate in a deviation or delay in neurological
development that is thought to underlie the prob-
lem and risky behaviours that often precede
substance use. Understanding the neurobiological
contribution to the aetiology of substance use
involves characterizing the brain maturation pro
-
cesses that occur during adolescence, such as reduced
inhibitory control and increased reward sensitivity,
and are associated with substance use.
Substance use and harmful use of substances are the
result of a developmental process beginning in the
prenatal period and lasting until a person is in their
mid- to late 20s. Data from surveys on drug use
indicate that initiation of substance use is most
common in early to mid-adolescence and, for the
subgroup of users that escalate, substance use peaks
during the transition into young adulthood.
76
Criti-
73 Maria Kovacs and David Goldston, “Cognitive and
social cognitive development of depressed children and
adolescents”, Journal of the American Academy of Child and
Adolescent Psychiatry, vol. 30, No. 3 (1991), pp. 388–392.
74 United States, National Institute on Drug Abuse,
“Comorbidity: addiction and other mental illnesses”, NIDA
Research Report Series, NIH Publication No. 10–5771
(Washington, D.C., 2010).
75 Kristin L. Tomlinson, Sandra Brown and Ana Abrantes,
“Psychiatric comorbidity and substance use treatment
outcomes of adolescents”, Psychology of Addictive Behaviors,
vol. 18, No. 3 (2004), pp. 160–169.
76 Rachel N. Lipari and others, “Risk and protective factors
and estimates of substance use initiation: results from the
2016 National Survey on Drug Use and Health”, NSDUH
Data Review (September 2017).
Behavioural and mental health
The co-occurrence of mental health and substance
use disorders afflicts millions of people, according
to data from multiple sources, including WHO.
Specifically, internalizing symptoms such as post-
traumatic stress disorder, depression and anxiety,
along with externalizing behaviours such as conduct
disorder, attention-deficit hyperactivity disorder,
oppositional defiant disorder, antisocial personality
disorder and certain other mental health conditions,
are strongly and consistently related to the risk of
harmful use of substances.
68
Individuals with these
disorders are in general more likely to use substances
and to do so at an earlier age than those without.
69,
70
Mood and anxiety disorders, for example, double
the risk of an individual developing substance use
disorders.
71
The presence of mental and behavioural health dis-
orders may exacerbate the role of poor or maladaptive
stress reactivity patterns in the developmental path-
ways to substance use. Individuals with internalizing
disorders tend to have higher levels of arousal in the
brain systems that are responsible for stress responses,
which may lead to a tendency to self-medicate the
symptoms of anxiety and depression.
72
Those with
externalizing disorders tend to have a lower level of
arousal in these systems, which has been associated
with a relative lack of regard for consequences and
a need for additional stimulation.
The likelihood of a person with conditions such as
post-traumatic stress disorder or attention-deficit
approaches to the treatment of nicotine dependence”,
Oncogene, vol. 21, No. 48 (2002), pp. 7412–7420.
68 Tonya D. Armstrong, and Jane E. Costello, “Community
studies on adolescent substance use, abuse, or dependence
and psychiatric comorbidity”, Journal of Consulting and
Clinical Psychology, vol. 70, No. 6 (2002), pp. 1224–1239.
69 Michael D. De Bellis and others, “Brain structures in
pediatric maltreatment-related posttraumatic stress disorder:
a sociodemographically matched study” Biological Psychiatry,
vol. 52, No. 11 (2002), pp. 1066–1078.
70 Cynthia L. Rowe and others, “Impact of psychiatric
comorbidity on treatment of adolescent drug abusers”,
Journal of Substance Abuse Treatment, vol. 26, No. 2 (2004),
pp. 129–140.
71 Susan B. Quello and others, “Mood disorders and substance
abuse disorders: a complex comorbidity”, Science and
Practice Perspectives, vol. 3, No. 1 (2005), pp. 13–21.
72 Andrea M. Hussong and others, “An internalizing pathway
to alcohol use and disorder”, Psychology of Addictive
Behaviors, vol. 25, No. 3 (2011), pp. 390–404.
DRUGS AND AGE B. Drugs and young people
27
4
In addition, brain circuits, such as ventral striatum,
that are involved in processing rewards, show rapid
maturation during the adolescent years, heightening
sensitivity to rewarding experiences.
82, 83, 84
This
development may play a unique role in the initia-
tion of substance use in early to mid-adolescence
and may be exaggerated in the subgroup that escalate
use. Subsequent use of substances may exacerbate
some adolescents’ already heightened reward sensi-
tivity, resulting in a strengthening of the drug’s
reinforcing properties.
85
Together with this increase
in reward sensitivity, adolescence brings a series of
other characteristics to the development process that
compromise neurodevelopment and can cause meas-
urable dysfunction in the brain systems. These
include:
•
A greater tendency to sensation- and
novelty-seeking
•
Early puberty and erratic hormone levels
•
Detrimental environmental conditions such as
stress, adversity, maltreatment and other nega-
tive experiences
86
adulthood”, Frontiers in Psychology, vol. 2, art. 39 (2011).
82 A. Padmanabhan and others, “Developmental changes
in brain function underlying the influence of reward
processing on inhibitory control”, Developmental Cognitive
Neuroscience, vol. 1, No. 4 (2011), pp. 517–529.
83 C. F. Geier and others, “Immaturities in reward processing
and its influence on inhibitory control in adolescence”,
Cerebral Cortex, vol. 20, No. 7 (2010), pp. 1613–1629.
84 Somerville and Casey, “Developmental neurobiology of
cognitive control and motivational systems”.
85 Michael E. Hardin and Monique Ernst, “Functional brain
imaging of development-related risk and vulnerability for
substance use in adolescents”, Journal of Addiction Medicine,
vol. 3, No. 2 (2009), pp. 47–54.
86 Laurence Steinberg, “A dual systems model of adolescent
risk-taking”, Developmental Psychobiology, vol. 52, No. 3
cally, new social challenges, such as increased
autonomous decision-making, that adolescents face
coincide with complex changes in brain wiring and
connectivity that take place throughout this time.
These have implications for adaptive decision-mak-
ing and the ability to self-regulate behaviour and
emotion.
77
In effect, some degree of impulsivity,
risk-taking and sensation-seeking is normative
during adolescence, as indicated above. However, a
heightened level of risk-taking may extend from a
combination of social circumstances and non-nor-
mative neurodevelopmental immaturity or
dysfunction.
Neurobiological development during adolescence
occurs transitionally rather than as a single snapshot
in time.
78
The prefrontal cortex, the part of the
brain responsible for executive cognitive functions
such as decision-making, impulse control and
working memory, is still under construction. A
central function of these executive cognitive
functions is to shield long-term goals from
temptations afforded by short-term benefits that
often lead to negative consequences.
79
The prefrontal
“top-down” cognitive regulation over subcortical
regions is somewhat functionally disconnected
throughout adolescence. This translates into the
natural tendency of adolescents to act on emotional
stimuli, with little cognitive control.
80
Through
both the natural course of development and
environmental experience, connections between the
cognitive regulation and emotional stimuli regions
of the brain are strengthened, providing a mechanism
for increasing top-down regulation of emotional
brain systems.
81
77 Scott Marek and others, “The contribution of network
organization and integration to the development of
cognitive control”, PLoS Biology, vol. 13, No. 12 (2015).
78 B. J. Casey, Rebecca M. Jones and Hare A. Todd, “The
adolescent brain”, Annals of the New York Academy of
Sciences, vol. 1124, No. 1 (2008), pp. 111–126.
79 Maria Kharitonova and Yuko Munakata, “The role of
representations in executive function: investigating a
developmental link between flexibility and abstraction”,
Frontiers in Psychology, vol. 2, art. 347 (2011).
80 Leah H. Somerville and B. J. Casey, “Developmental
neurobiology of cognitive control and motivational
systems”, Current Opinion in Neurobiology, vol. 20, No. 2
(2010), pp. 236–241.
81 Nim Tottenham, Hare A. Todd and B. J. Casey, “Behavioral
assessment of emotion discrimination, emotion regulation,
and cognitive control in childhood, adolescence, and
Regardless of the source of delayed or deficient
neurodevelopment, the imbalance between social
demands and emergent neurobiological systems
during adolescence may lead to heightened vulner-
ability to substance use and escalation to harmful
use of substance. This evidence has direct implica-
tions for the design of intervention components that
target this period of development.
Source: B. J. Casey and R. M. Jones, “Neurobiology of
the adolescent brain and behavior: implications for
substance use disorder”, Journal of the American
Academy of Child and Adolescent Psychiatry, vol. 49,
No. 12 (December 2010).
28
WORLD DRUG REPORT 2018
demonstrated by the results of the Adverse Child-
hood Experiences study, as shown in table 2.
93, 94,
95
These findings suggest that very early develop-
ment sets the stage for response to initiation of
substance use by primary biological, psychological
and social responses to initiation.
Like all other risk factors, exposure to stress has dif-
ferential effects on social, psychological and neural
functioning and, in turn, on the risk of substance
use and harmful use, based on sex, genetic vulner-
abilities and developmental stages of exposure.
96, 97
In terms of sex differences, girls not only report a
greater number of negative life events during ado-
lescence than boys, but they are also more likely to
experience interpersonal stressors and be adversely
affected by them.
98
For example, post-traumatic
stress disorder often antedates drug use and harmful
drug use among girls but it occurs more often after
harmful substance use in boys, perhaps suggesting
93 Daniel P. Chapman and others, “Adverse childhood
experiences and the risk of depressive disorders in
adulthood”, Journal of Affective Disorders, vol. 82, No. 2
(2004), pp. 217–225.
94 Dube and others, “Childhood abuse, neglect, and
household dysfunction and the risk of illicit drug use”.
95 Robert F. Anda and others, “Adverse childhood experiences
and prescription drug use in a cohort study of adult HMO
patients”, BMC Public Health, 4 June 2008.
96 Kendler, Gardner and Prescott, “Personality and the
experience of environmental adversity”.
97 Susan L. Andersen and Martin H. Teicher, “Desperately
driven and no brakes: developmental stress exposure and
subsequent risk for substance abuse”, Neuroscience and
Biobehavioral Reviews, vol. 33, No. 4 (2009), pp. 516–524.
98 Xiaojia Ge
and others, “Parents’ stressful life events and
adolescent depressed mood”, Journal of Health and Social
Behaviour, vol. 35, No. 1 (1994), pp. 28–44.
Stress exposures and physiological reactivity
Stress is a major common denominator across the
neurobiological, physiological, psychological and
environmental domains implicated in susceptibility
to substance use, substance use escalation, relapse
and treatment resistance.
Numerous studies have demonstrated the associa-
tions between increasing levels of emotional and
physiological stress and decreases in behavioural
control, higher levels of impulsivity and high levels
of maladaptive behaviours.
87, 88, 89
There is also
substantial evidence to support the role of stress in
substance use pathways.
90, 91
Early life adversity in
particular is markedly associated with an increased
risk of substance use, harmful use and dependence.
92
This fundamental relationship is clearly
(2010), pp. 216–224.
87 Jumi Hayaki and others, “Adversity among drug users:
relationship to impulsivity”, Drug and Alcohol Dependence,
vol. 7778, No. 1 (2005), pp. 65–71.
88 Barbara Greco and Mirjana Carli, “Reduced attention and
increased impulsivity in mice lacking NPY Y2 receptors:
relation to anxiolytic-like phenotype”, Behavioural Brain
Research, vol. 169, No. 2 (2006), pp. 325–334.
89 Martin Hatzinger and others, “Hypothalamic–pituitary–
adrenocortical (HPA) activity in kindergarten children:
importance of gender and associations with behavioral/
emotional difficulties”, Journal of Psychiatric Research, vol.
41, No. 10 (2007), pp. 861–870.
90 Hanie Edalati and Marvin D. Krank, “Childhood
maltreatment and development of substance use disorders:
a review and a model of cognitive pathways” Trauma,
Violence, & Abuse, vol. 17, No. 5 (2016), pp. 454–467.
91 Christine M. Lee, Clayton Neighbors and Briana A.
Woods, “Marijuana motives: young adults’ reasons for using
marijuana”, Addictive Behaviors, vol. 32, No. 7 (2007), pp.
1384–1394.
92 Shanta R. Dube and others, “Childhood abuse, neglect, and
household dysfunction and the risk of illicit drug use: the
adverse childhood experiences study”, Pediatrics, vol. 111,
No. 3 (2003), pp. 564–572.
Early life adversity is markedly associated with
increased risk of substance use, harmful substance
use and drug dependence. Drug use may occur as
a maladaptive response to stressful experiences.
Table 2
Estimates of the population-attributable
risk of adverse childhood experiences
for selected outcomes among women
Population-attributable
risk of adverse
childhood experience
Substance
use
65 per cent Alcoholism
50 per cent Harmful use of drugs
78 per cent Injecting drug use
Stress refers to processes involving perception,
appraisal and response to harmful, threatening or
challenging external events or conditions, known
as “stressors”, such as poverty, prenatal exposures,
child maltreatment, divorce and bereavement.
Source: A. Levine and others, “Molecular mechanism
for a gateway drug: epigenetic changes initiated by
nicotine prime gene expression by cocaine”, Science
Translational Medicine, vol. 3, No. 107 (November
2011).
DRUGS AND AGE B. Drugs and young people
29
4
stress responses activate the same neural systems that
underlie the positive reinforcing effects of drugs,
107
potentially reinforcing drug-taking behaviours. As
a result, drug taking may occur as a maladaptive
response to stressful experiences. Recognizing the
increased risk of substance use in young people who
have experienced early life stressors is critical to guide
efforts designed to both prevent exposure to and
counteract the potential subsequent negative con-
sequences of substance use.
Epigenetics, genetic variations and response to social
influences
Genetic variations contribute to a determination of
an individual’s response to prevailing social influ-
ences; genetic influences on propensity to substance
use and substance use disorders are thought to be
mediated by individual characteristics in interaction
with environmental factors, with stress exposures
having a particular impact.
108
At the core of the
interaction between genes and the environment are
epigenetic modifications that occur at the level of
gene activities in response to changes in the envi-
ronment. Adverse experiences, especially in early
life, have the potential to modify gene expression
or suppression, which has important implications
for phenotypic impact on stress hormones and
behaviour.
109
Ongoing environmental change can
further modify epigenetic processes, for better or
for worse, helping to explain individual differences
in response to stress as well as the potential for posi-
tive environmental change, for example through
intervention, to reverse earlier negative modifica-
tions. As indicated in the “conceptual model” (figure
8 on page 23), not all people who are exposed to
stress or trauma will exhibit maladaptive physiologi-
cal and psychological stress responses that affect
substance use and harmful use of substance.
vol. 10, No. 4 (1998), pp. 793–809.
107 George F. Koob and Michel Le Moal, “Drug abuse: hedonic
homeostatic dysregulation”, Science, vol. 278, No. 5335
(1997), pp. 52–58.
108 Mary-Anne Enoch, “The influence of gene–environment
interactions on the development of alcoholism and drug
dependence”, Current Psychiatry Reports, vol. 14, No. 2
(2012), pp. 150–158.
109 Moshe Szyf and others, “The dynamic epigenome and
its implications for behavioral interventions: a role for
epigenetics to inform disorder prevention and health
promotion”, Translational Behavioral Medicine, vol. 6, No. 1
(2016), pp. 55–62.
that females are more likely to self-medicate their
symptoms, whereas males may be more likely to
experience trauma owing to the risk situations asso-
ciated with harmful substance use.
99
Females are
also at increased risk of harmful substance use when
exposed to the stressors of family violence and alco-
holism.
100
These findings and many others reveal
sex differences in the exposure to and experience of
trauma and stress, as well as the differential influ-
ence of sex on substance use patterns, and suggest
that gender aspects should be considered in etiologi-
cal research and in the development of a prevention
intervention or treatment plan.
Research shows that early life stress predisposes indi-
viduals to use substances later because the stressors
have an impact on immature neurophysiological
systems. In adolescence, when these emergent sys-
tems become increasingly functional, the damage is
expressed in heightened risk of psychopathology.
101
Greater levels of stress also affect adolescents’ already
lowered behavioural and cognitive controls.
102, 103
Stress exposures disrupt both the hormonal and the
physiological systems that regulate these functions,
impairing learning, memory, decision-making and
other functions that normally support the self-reg-
ulation of behaviour.
104, 105, 106
These biological
99 Eva Y. Deykin and Stephen L. Buka, “Prevalence and risk
factors for posttraumatic stress disorder among chemically
dependent adolescents”, American Journal of Psychiatry, vol.
154, No. 6 (1997), pp. 752–757.
100 Stephen T. Chermack, Brett E. Fuller and Frederic C. Blow,
“Predictors of expressed partner and non-partner violence
among patients in substance abuse treatment”, Drug &
Alcohol Dependence, vol. 158, Nos. 1 and 2 (2000), pp.
43–54.
101 Andersen and Teicher, “Desperately driven and no brakes”.
102 Susan L. Andersen and Martin H. Teicher, “Stress, sensitive
periods and maturational events in adolescent depression”,
Trends in Neurosciences, vol. 31, No. 4 (2008), pp. 183–191.
103 Rajita Sinha, “How does stress increase risk of drug abuse
and relapse?”, Psychopharmacology, vol. 158, No. 4 (2001),
p. 343.
104 Gerald Heuther, “Stress and the adaptive self-organization
of neuronal connectivity during early childhood”,
International Journal of Developmental Neuroscience, vol. 16,
Nos. 3 and 4 (June/July 1998), pp. 297–306.
105 William R. Lovallo and others, “Lifetime adversity leads to
blunted stress axis reactivity: studies from the Oklahoma
family health patterns project”, Biological Psychiatry, vol. 71,
No. 4 (2012), pp. 344–349.
106 C. A. Nelson and L. J. Carver, “The effects of stress and
trauma on brain and memory: a view from developmental
cognitive neuroscience”, Development and Psychopathalogy,
30
WORLD DRUG REPORT 2018
cannot be underestimated.
113
Parenting that is
harsh, restrictive, inconsistent, hostile and/or high
in conflict can often lead to negative behavioural
outcomes in children.
114
At the extreme of parenting behaviour, abuse,
neglect and domestic violence, in particular, threaten
every aspect of children’s development. The quality
of parenting further interacts with factors such as
psychological well-being, exposure to stress and
social support in predicting general antisocial behav-
iour, as well as substance use and substance use
disorders.
115
Parenting can exacerbate the risk of substance use
as early as infancy, particularly for babies with a
“difficult” temperament. These early signs are often
manifested as irritability, frequent crying, with-
drawal from affection, irregular sleeping or eating
patterns, and inability to soothe. Such problems
commonly originate in genetic, congenital and pre-
natal processes.
116
Babies with hard-to-manage
temperaments may elicit negative responses such as
rejection, ineffective practices, harsh discipline, mal-
treatment or substance use on the part of their
caregivers. Any of these responses can exacerbate
113 Melissa A. Lippold and others, “Unpacking the effect of
parental monitoring on early adolescent problem behavior:
mediation by parental knowledge and moderation by
parent-youth warmth”, Journal of Family Issues, vol. 35, No.
13 (2014), pp. 1800–1823.
114 Anne E. Barret and R. Jay Turner, “Family structure and
mental health: the mediating effects of socioeconomic
status, family process, and social stress”, Journal of Health
and Social Behavior, vol. 46, No. 2 (2005), pp. 156–169.
115 Benjamin J. Hinnant, Stephen A. Erath and Mona
El-Sheikh, J “Harsh parenting, parasympathetic activity,
and development of delinquency and substance use”,
Journal of Abnormal Psychology, vol. 124, No. 1 (2015), pp.
137–151.
116 Lyndall Schumann and others, “Persistence and innovation
effects in genetic and environmental factors in negative
emotionality during infancy: a twin study”, PLoS ONE, vol.
12, No. 4 (2017).
While genes do not increase the risk of using or of
developing harmful use of specific substances, there
is evidence that they do affect neurobiological
systems and phenotypic traits that more directly
influence pathways to or from substance use. These
systems and traits fundamentally interact with stress
exposures that, when they are repeated or if they are
severe, have the potential to compromise the
development of neural systems that underlie social,
behavioural, cognitive and emotional functioning
in profound and enduring ways.
110, 111
Micro-level influences
Substance use among young people cannot be
understood or addressed without comprehending
the social context within which individuals grow,
develop and interact. Contextual factors that may
vary across cultures can accentuate the relations
between parenting and family, peer influences,
pubertal timing and problem outcomes such as sub-
stance use, in ways that differ between the sexes. In
the present subsection, both the liability factors that
influence problem behaviour and the environmental
conditions that may insulate individuals from nega-
tive outcomes are considered.
Parenting and family functioning
Parenting and the home environment exert pro-
found influences on early child development in
multiple domains of functioning.
112
The strength
of parental influence on substance use, for example,
110 Robin Davidson, “Can psychology make sense of change?”,
in Addiction: Processes of Change, Griffith Edwards and
Malcom H. Lader, eds., Society for the Study of Addiction
Monograph No. 3 (New York, Oxford University Press,
1994).
111 Pia Pechtel and Diego A. Pizzagalli, “Effects of early life
stress on cognitive and affective function: an integrated
review of human literature”, Psychopharmacology, vol. 214,
No. 1 (2011), pp. 55–70.
112 United States, National Research Council and Institute of
Medicine of the National Academies, Preventing Mental,
Emotional, and Behavioral Disorders Among Young People:
Progress and Possibilities, Mary E. O’Connell, Thomas Boat
and Kenneth E. Warner, eds. (Washington, D.C., National
Academies Press, 2009).
Different susceptibility to harmful substance use is a
function of the complex interrelationships between
genetic, environmental and epigenetic factors that
individuals experience dynamically.
Children exposed to negative parenting qualities are
two to four times more likely to develop mental and
physical health issues than those within the norms.
Source: T. I. Herrenkohl and others, “Family influences
related to adult substance use and mental health
problems: a developmental analysis of child and ado-
lescent predictors”, The Journal of Adolescent Health,
vol. 51, No. 2 (February 2012), pp. 129–135.
DRUGS AND AGE B. Drugs and young people
31
4
families, which is consistent with studies reporting
that dual-parent families better afford protection
against substance use.
122
This finding could be the
result of the lack of a protective presence of an addi
-
tional person in the home who can protect the child
from stress exposure and lack of monitoring.
Parenting and the home environment continue to
be important when adolescents begin to have more
autonomy and opportunities for either prosocial or
risky behaviours.
123
The effects of a chaotic home
environment, ineffective parenting and lack of
mutual attachment in particular have an impact on
overall child outcomes.
124
This scenario may par-
ticularly affect girls, who tend to be more sensitive
to family-centred and relational problems.
125, 126
This could heighten susceptibility among girls to
stress and mental health issues, including early onset
of substance use and harmful use, as well as other
risky behaviours.
Schools and educational opportunities
The quality of the school environment, teachers,
the curriculum and students’ social networks in
school are major socializing influences on student
122 Gunilla R. Weitoft and others, “Mortality, severe morbidity,
and injury in children living with single parents in Sweden:
a population-based study”, Lancet, vol. 361, No. 9354
(2003), pp. 289–295.
123 Monique Ernst and Sven C. Muller, “The adolescent
brain: insights from functional neuroimaging research”,
Developmental Neurobiology, vol. 68, No. 6 (2008), pp.
729–743.
124 Kristen W. Springer and others, “Long-term physical and
mental health consequences of childhood physical abuse:
results from a large population-based sample of men and
women”, Child Abuse and Neglect, vol. 31, No. 5 (2007),
pp. 517–530.
125 Jennifer Connolly and others, “Conceptions of cross-sex
friendships and romantic relationships in early adolescence”,
Journal of Youth and Adolescence, vol. 28, No. 4 (1999), p.
481.
126 Eleanor E. Maccoby, The Two Sexes: Growing Up Apart,
Coming Together (Cambridge, Massachusetts, Harvard
University Press, 1999).
this developmental process.
117
This scenario can be
particularly impactful in the context of pre-existing
dysfunction or hardship in the caregivers, such as
mental illness, harmful use of substances, antisocial
behaviour or poverty.
118, 119
In addition, more “dif-
ficult” children can provoke harsher and less effective
responses even from caregivers with the psychologi-
cal wherewithal or physical resources to cope with
their baby’s special problems and needs. Once the
caregiver-child relationship is strained, there is often
less warmth, attachment and effective coping, fur-
ther heightening the child’s risk for maladaptive
behaviours. In short, the child’s responses stimulate
predictable reactions from the social environment.
This may reinforce or counteract the child’s reac-
tions, thus contributing to further changes in
reactions from both the social environment and the
child. This “action-reaction” sequence places the
child at increased risk for long-term social malad-
justment and risky behaviours. Rather than replacing
one behaviour with another in response to changing
socioenvironmental conditions, however, behaviours
tend to diversify and can strengthen, weaken or
reverse the developmental path over time.
In addition to parenting, various aspects of the family
environment can influence a child’s subsequent sub-
stance use behaviour. These can include structural
characteristics, family cohesion, family communica-
tion and family management.
120
Family processes
that tend to be the most averse are those with high
levels of stress exposure and coercion.
121
Addition-
ally, greater tendencies towards substance use have
been found in adolescents from single-parent
117 Kerry Lee, Rebecca Bull and Ringo M. Ho,
“Developmental changes in executive functioning”, Child
Development, vol. 84, No. 6 (2013), pp. 1933–1953.
118 Thomas G. O’Connor and others, “Co-occurrence of
depressive symptoms and antisocial behavior in adolescence:
a common genetic liability”, Journal of Abnormal Psychology,
vol. 107, No. 1 (1998), pp. 27–37.
119 Thomas G. O’Connor, and others, “Genotype-environment
correlations in late childhood and early adolescence:
antisocial behavioral problems and coercive parenting”,
Developmental Psychology, vol. 34, No. 5 (1998), pp. 970–
981.
120 Richard D. B. Velleman, Lorna J. Templeton and Alex
G. Copello, “The role of the family in preventing and
intervening with substance use and misuse: a comprehensive
review of family interventions, with a focus on young
people”, Drug and Alcohol Review, vol. 24, No. 2 (2005),
pp. 93–109.
121 Barret and Turner, “Family structure and mental health”.
The regulatory skills that children need to resist
substance use and other problem behaviours are
instilled early in life, suggesting that a favourable
home environment (family cohesion, family commu-
nication, and family management) confer protection
against negative outcomes, including substance use.
32
WORLD DRUG REPORT 2018
problems and an increased likelihood of using sub-
stances in early secondary school when they report
low school connectedness, and interpersonal con-
flict.
135, 136
Peer influences and substance use
There is a strong association between adolescent
substance use and contact with substance-using
peers. Research suggests that other adolescents pro-
vide a unique source of access to drugs, reinforcement
and opportunity to use drugs.
137, 138, 139
Adoles-
cents tend to display similar behaviours, attitudes
and personality traits to their friends.
140
Studies
suggest that adolescents who choose substance-using
friends may differ from those who do not. The qual-
ity of the friendship also seems to be a factor in
determining the extent to which an individual may
be influenced by a friend: a high-quality relation-
ship may be more valued by an adolescent, who may
be more likely to change their behaviour to please
the friend. Closer friends may spend more time
together, resulting in more modelling and emula-
tion of high-risk behaviour. One of the ways in
135 Bond and others, “Social and school connectedness in early
secondary school as predictors of late teenage substance use,
mental health, and academic outcomes”.
136 Richard F. Catalano and others, “Positive youth
development in the United States: research findings on
evaluations of positive youth development programs”,
Annals of the American Academy of Political and Social
Science, vol. 591, No. 1 (2004).
137 Deirdre M. Kirke, “Chain reactions in adolescents’
cigarette, alcohol, and drug use: similarity through peer
influence or the patterning of ties in peer networks?”, Social
Networks, vol. 26, No. 1 (2004), pp. 3–28.
138 Bruce G. Simons-Morton and Tilda Farhat, “Recent
findings on peer group influences on adolescent smoking”,
Journal of Primary Prevention, vol. 31, No. 4 (2010), pp.
191–208.
139 Kathryn A. Urberg and others, “A two-stage model of
peer influence in adolescent substance use: individual
and relationship-specific differences in susceptibility to
influence”, Addictive Behaviors, vol. 28, No. 7 (2003), pp.
1243–1256.
140 Ibid.
learning and behaviour.
127, 128
At a very basic level,
absence from school through truancy, suspension
or expulsion increases the risk of poor outcomes on
multiple levels; chronic absenteeism may be espe-
cially problematic for children with self-regulatory
problems.
129
Moreover, unqualified teachers, inef-
fective teaching practices and low-quality curricula
confer significant additional risks, leading to aca-
demic failure.
130, 131
Lack of a good education and
poor classroom management sets the stage for lower
levels of cognitive functioning, poor social skills,
high levels of stress and perceptions of inadequacy
and failure,
132
each of which is implicated in risk
of substance use. Absence of adequate educational
support and/or targeted school programmes, learn-
ing disabilities and mental health problems further
compound the risk of substance use and harmful
substance use.
133
In the longer term, a poor-quality
education results in an inability to compete in the
workforce and obtain jobs that pay a good wage,
134
factors also associated with later substance use.
Another aspect of school influences is the important
role of school connectedness. Research suggests that
young people are more likely to have mental health
127 Lyndal Bond and others, “Social and school connectedness
in early secondary school as predictors of late teenage
substance use, mental health, and academic outcomes”,
Journal of Adolescent Health, vol. 40, No. 4 (2007), pp. 357.
e9-357.e18.
128 H. Harrington Cleveland and Richard P. Wiebe,
“Understanding the association between adolescent
marijuana use and later serious drug use: gateway effect or
developmental trajectory?” Development and Psychopathology,
vol. 20, No. 2 (2008,), pp. 615 –632.
129 Christine A. Christle, Kristine Jolivette and C. Michael
Nelson, “Breaking the school to prison pipeline: identifying
school risk and protective factors for youth delinquency”,
Exceptionality, vol. 13, No. 2 (2005), pp. 69–88.
130 Ibid.
131 L. Darling-Hammond, “How teacher education matters”,
Journal of Teacher Education, vol. 51, No. 3 (2000), pp.
166–173.
132 Patrice L. Engle and Maureen M. Black, “The effect of
poverty on child development and educational outcomes”,
Annals of the New York Academy of Sciences, vol. 1136, No. 1
(2008), pp. 243–256.
133 Michael J. Mason and Jeremy Mennis, “An exploratory
study of the effects of neighborhood characteristics on
adolescent substance use”, Addiction Research and Theory,
vol. 18, No. 1 (2010), pp. 33–50.
134 Frances A. Campbell and others, “Early childhood
education: young adult outcomes from the Abecedarian
project”, Applied Developmental Science, vol. 6, No. 1
(2002), pp. 42–57.
A child’s attachment to school appears to be a com-
ponent of resilience (a protective factor), indicating
that effective and responsive teachers, evidence-
based curricula and classroom reinforcements may
play an important role in the prevention of sub-
stance use.
DRUGS AND AGE B. Drugs and young people
33
4
associated with increased conflict among parents
and adolescents with regard to issues such as selec-
tion of friends or dating and to shifting behavioural
expectations
149, 150, 151
that can lead to more con-
duct problems, exposure to peer deviance and risky
sexual behaviours.
152
Furthermore, residing in a
disadvantaged neighbourhood appears to further
exacerbate the effect of peers for both sexes.
153, 154
Macro-level influences
The neighbourhood, the physical environment and the
media
Social conditions in neighbourhoods have major
implications for risk of substance use as they shape
social norms, enforce patterns of social control,
influence perception of the risk of substance use and
affect psychological and physiological stress respons-
es.
155
One aspect of neighbourhood influence is
social cohesion, an indicator of attachment to and
satisfaction with the neighbourhood and its residents
that involves trust and support for one another in
a community.
It has been suggested that high levels of social cohe-
sion are associated with lower levels of substance use
(New York, Cambridge University Press, 2003), pp.
241–276.
149 Xiaojia Ge, Rand D. Conger and Glen H. Elder Jr.,
“Coming of age too early: pubertal influences on girls’
vulnerability to psychological distress”, Child Development,
vol. 67, No. 6 (1996), pp. 3386–3400.
150 Roberta L. Paikoff and Jeanne Brooks-Gunn, “Do parent-
child relationships change during puberty?, Psychological
Bulletin, vol. 110, No. 1 (1991), pp. 47–66.
151 Lynda M. Sagrestano and others, “Pubertal development
and parent-child conflict in low-income, urban, African
American adolescents”, Journal of Research on Adolescence,
vol. 9, No. 1 (2010), pp. 85–107.
152 Dana L. Haynie, “Contexts of risk? Explaining the link
between girls’ pubertal development and their delinquency
involvement”, Social Forces, vol. 82, No. 1 (2003), pp.
355–397.
153 Xiaojia Ge and others, “It’s about timing and change:
pubertal transition effects on symptoms of major depression
among African American youths”, Developmental Psychology,
vol. 39, No. 3 (2003), pp. 430–439.
154 Dawn Obeidallah and others, “Links between pubertal
timing and neighborhood contexts: implications for girls’
violent behaviour”, Journal of the American Academy of
Child and Adolescent Psychiatry, vol. 43, No. 12 (2004), pp.
1460–1468.
155 Elvira Elek, Michelle Miller-Day and Michael L. Hecht,
“Influences of personal, injunctive, and descriptive norms
on early adolescent substance use”, Journal of Drug Issues,
vol. 36, No. 1 (2006), pp. 147–172.
which peers appear to influence one another is
through the idea of “pluralistic ignorance”,
141
whereby the general belief that more individuals are
engaging in substance use than actually are may
contribute to their own use of substances.
142, 143
Conversely, those who believe substance use will
have harmful consequences are less likely to engage
in such use.
144
There also appear to be some distinctive ways in
which girls are influenced by peers to use substances.
For example, they are more susceptible to social
pressures when the source is a friend or partner.
145
Girls also tend to have a greater level of sensitivity
to peer approval, depression and body image, which
are all interrelated and can increase the risk of sub-
stance use.
146
Early pubertal development in girls
can also play a role; for example, early-maturing
girls are more likely to spend time with older males,
who are inclined towards risk-taking activities and
may introduce them to the use of substances.
147,
148
Pubertal onset, in particular among girls, is also
141 Deborah A. Prentice and Dale T. Miller, “Pluralistic
ignorance and alcohol use on campus: some consequences
of misperceiving the social norm”, Journal of Personality and
Social Psychology, Vol. 64, No. 2 (1993), pp. 243–256.
142 Mitchell J. Prinstein and Shriley S. Wang, “False consensus
and adolescent peer contagion: examining discrepancies
between perceptions and actual reported levels of friends’
deviant and health risk behaviors”, Journal of Abnormal
Child Psychology, vol. 33, No. 3 (2005), pp. 293–306.
143 Sarah L.Tragesser, Patricia A. Aloise-Young and Randall
C. Swaim, “Peer influence, images of smokers, and beliefs
about smoking among preadolescent nonsmokers”, Social
Development, vol. 15, No. 2 (2006), pp. 311–325.
144 National Centre on Addiction and Substance Abuse,
Columbia University, Adolescent Substance Use: America’s #1
Public Health Problem (New York, June 2011).
145 Vera Frajzyngier and others, “Gender differences in
injection risk behaviors at the first injection episode”, Drug
and Alcohol Dependence, vol. 89, Nos. 2 and 3 (2007), pp.
145–152.
146 Steven P. Schinke, Lin Fang and Kristin C. A. Cole,
“Substance use among early adolescent girls: risk and
protective factors”, Journal of Adolescent Health, vol. 43, No.
2 (2008), pp. 191–194.
147 David Magnusson and L. R. Bergman, “A pattern approach
to the study of pathways from childhood to adulthood”, in
Straight and Devious Pathways from Childhood to Adulthood,
Lee N. Robins and Michael Rutter, eds. (Cambridge,
Cambridge University Press, 1990), pp. 101–115.
148 Karina Weichold, Rainer K. Silbereisen and Eva Schmitt-
Rodermund, “Short-term and long-term consequences
of early versus late physical maturation in adolescents”,
in Gender Differences at Puberty, Chris Hayward, ed.,
Cambridge Studies on Child and Adolescent Health Series
34
WORLD DRUG REPORT 2018
disorders.
161
Such exposure has also been linked to
later risk of harmful substance use, as well as other
forms of psychopathology. Although the research is
scant with respect to its direct association with sub-
stance use, such exposure is more definitively related
to the personal characteristics, such as psychiatric
disorders, lack of impulse control or cognitive defi-
cits, that are known to increase the risk of substance
use and harmful use of substances.
The media is a powerful influence on social norms
and other messages that are favourable to substance
use.
162
Adolescents in particular spend a great deal
of time using the Internet, messaging services and
social media, in particular on smartphones, as well
as being entertained by television, movies and other
media. Media portrayals of substance use as glam-
orous, fun and relaxing all contribute to the
initiation and continued use of psychoactive sub-
stances among young people.
163
In essence, certain
media messages can make substance use appear to
be normative behaviour and can alter attitudes about
the safety of substance use. Social media has been
repeatedly linked to the initiation of substance
use;
164, 165
for example, a study in the United States
found an association between exposure to cannabis
in popular music and initiation of its use among
adolescents.
166
Income and resources
Other macro-level influences include degrees of pov-
erty that young people experience in their
communities. A growing body of evidence has been
161 David C. Bellinger, “A strategy for comparing the
contributions of environmental chemicals and other risk
factors to neurodevelopment of children”, Environmental
Health Perspectives, vol. 120, No. 4 (2002), pp. 501–507.
162 Emily C. Feinstein and others, “Addressing the critical
health problem of adolescent substance use through health
care, research, and public policy”, Journal of Adolescent
Health, vol. 50, No. 5 (2012), pp. 431–436.
163 Ibid.
164 Chrstine McCauley Ohannessian and others, “Social
media use and substance use during emerging adulthood”,
Emerging Adulthood, vol. 5, Issue 5 (2017), pp. 364–370.
165 Caitlin R. Costello and Danielle E. Ramo, “Social media
and substance use: what should we be recommending to
teens and their parents?”, Journal of Adolescent Health, vol
60, Issue 6, (2017) pp. 629–630.
166 Brian A. Primack and others, “Exposure to cannabis in
popular music and cannabis use among adolescents”,
Addiction, vol. 105, (2009), pp. 515–523.
among adolescents, fewer perceived youth drug
problems and fewer drug-related deaths.
156
The
extent to which the neighbourhood is perceived as
disorganized or disordered or is an area character-
ized by vandalism, abandoned buildings and lots,
graffiti, noise and dirt may also influence levels of
substance use among adolescents. The neighbour-
hood context has been found to be particularly
influential for young people living in low-income
urban areas owing to the high level of exposure to
drug activity, disorder and violence in their neigh-
bourhoods, all of which may influence substance
use among young people.
157, 158
Many aspects of
the physical design of the environment can also
harm young people’s overall development and social
relations and lead to the commission of crime and
to substance use.
159, 160
A high level of exposure to toxic substances such as
heavy metals, in utero alcohol, lead, cadmium, mer-
cury, manganese or arsenic is another aspect of the
physical environment that can harm overall devel-
opment. During the prenatal period and early
childhood, such exposure has been shown to be
strongly and consistently linked to functional defi-
cits such as cognitive dysfunction and psychological
156 Peter Anderson and Ben Baumberg, Alcohol in Europe: A
Public Health Perspective, (London, Institute of Alcohol
Studies, 2006).
157 Anne Buu and others, “Parent, family, and neighborhood
effects on the development of child substance use and other
psychopathology from preschool to the start of adulthood”,
Journal of Studies on Alcohol and Drugs, vol. 70, No. 4
(2009), pp. 489–498.
158 Sharon F. Lambert and others, “The relationship between
perceptions of neighborhood characteristics and substance
use among urban African American adolescents”, American
Journal of Community Psychology, vol. 34, Nos. 3 and 4
(2004), pp. 205–218.
159 Tama Leventhal and Jeanne Brooks-Gunn, “The
neighborhoods they live in: the effects of neighborhood
residence on child and adolescent outcomes”, Psychological
Bulletin, vol. 126, No. 2 (2000), pp. 309–337.
160 National Research Council and Institute of Medicine, From
Neurons to Neighborhoods: The Science of Early Childhood
Development, Jack P. Shonkoff and Deborah A. Phillips, eds.
(Washington, D.C., National Academies Press, 2000).
Decayed and abandoned buildings, ready access to
alcohol and other drugs, urbanization and neigh-
bourhood deprivation are associated with drugs,
crime, violence and accidents.
DRUGS AND AGE B. Drugs and young people
35
4
an impoverished and unsupportive environment
impedes growth, leads to dysregulated physiological
responses to stressful situations, increases the risk of
psychological disorders such as depression, anxiety
and traumatic stress disorders and compromises the
development of self-regulatory skills: these are all
factors that increase vulnerability to substance use.
Young people who experience extreme poverty or a
lack of resources are subject to a host of environ-
mental and health factors including homelessness,
street involvement, exposure to toxic substances and
work at a young age. As a result, there is a high inci
-
dence of behavioural and psychological problems,
including use and harmful use of substances, among
these young people.
172, 173
In terms of implications
for prevention, high-quality caregiving moderates
the effects of poverty on child development,
174
in
particular for girls.
175
Increased availability of ser-
vices for disadvantaged children can foster their
potential to develop skills that would improve their
chances of success in school and life and combat
many of the risk factors for substance use.
176
Discrimination and social exclusion
Another macro-level factor affecting child develop-
ment is discrimination and social exclusion, which
arise from structural and cultural perspectives. Struc-
tural inequalities lead to adverse educational, health
and behavioural outcomes and are largely the result
and physical health of offspring”, Psychological Bulletin, vol.
128, No. 2 (2002), pp. 330–366.
172 H. Meltzer and others, “Victims of bullying in childhood
and suicide attempts in adulthood”, European Psychiatry,
vol. 26, No. 8 (2011), pp. 498–503.
173 Nada and Suliman, “Violence, abuse, alcohol and drug use,
and sexual behaviors in street children of Greater Cairo and
Alexandria, Egypt”.
174 Gary W. Evans, John Eckenrode and Lyscha A.
Marcynyszyn, “Chaos and the macrosetting: the role
of poverty and socioeconomic status”, in Chaos and
its Influence on Children’s Development: An Ecological
Perspective, Gary W. Evans and Theodore D. Wachs, eds.
(Washington, D.C., American Psychological Association,
2010), pp. 225–238.
175 Karol L. Kumpfer and others, “Cultural adaptation process
for international dissemination of the strengthening families
program”, Evaluation and the Health Professions, vol. 31, No.
2 (2008), pp. 226–239.
176 Angela Hudson and Karabi Nandy, “Comparisons of
substance abuse, high-risk sexual behavior and depressive
symptoms among homeless youth with and without a
history of foster care placement”, Contemporary Nurse, vol.
42, No. 2 (2014), pp. 178–186.
amassed to aid understanding of how overall condi-
tions in impoverished communities lead to
considerable delays or deficits in child and adoles-
cent development.
167
On an individual level, the influence of poverty on
families and parenting can lead to harmful effects
on child and youth development by increasing stress
among parents and caregivers, reducing their ability
to invest in learning and educational opportunities
and compromising their ability to be involved,
patient, responsive and nurturing parents to their
children.
168
These conditions — both individually
and through their interaction — are risk factors for
substance use.
169
The caregiving environment for
children in low-income families is more likely to be
disorganized and lacking in appropriate stimulation
and support, thereby creating conditions that are
stressful for children.
170, 171
Stress in the context of
167 Clancy Blair, “Stress and the development of self-regulation
in context”, Child Development Perspectives, vol. 4, No. 3
(2010), pp. 181–188.
168 Kenneth R. Ginsburg, “The importance of play in
promoting healthy child development and maintaining
strong parent-child bonds”, Pediatrics, vol. 119, No. 1
(2007), pp. 182–191.
169 Aurora P. Jackson and others, “Single mothers in low-
wage jobs: financial strain, parenting, and preschoolers’
outcomes”, Child Development, vol. 71, No. 5 (2000), pp.
1409–1423.
170 Gary W. Evans, “The environment of childhood poverty”,
American Psychologist, vol. 59, No. 2 (2004), pp. 77–92.
171 Rena L. Repetti, Shelley E. Taylor and Teresa E. Seeman,
“Risky families: family social environments and the mental
Among the main risk factors for
substance use in impoverished
neighbourhoods are:
• A high proportion of single-parent families
• Racial segregation and inequality based on
race, sex or other characteristics
• Homelessness
• Transiency and malnutrition
• Poorly equipped schools and poorly trained
teachers
• High levels of child abuse and infant mortality
• High school dropout rates, academic failure,
crime, delinquency and mental illness
36
WORLD DRUG REPORT 2018
was described in the 1990s in different settings
among young people and adults with refugee status:
khat chewing among conflict-affected Somali refu-
gees, opioid use among Afghan refugees in Iran
(Islamic Republic of) and Pakistan, non-medical
use of benzodiazepines among displaced people in
Bosnia and Herzegovina an use of methampheta-
mine among refugees from Myanmar in
Thailand.
180
Consequences for young people who
use drugs
Research on substance use among adolescents and
young adults suggests that chronic use of substances
among Latino immigrant parents in the USA”, Social
Science and Medicine, vol. 73, No. 8 (1982), pp. 1169–
1177.
180 Nadine Ezard and others, “Six rapid assessments of alcohol
and other substance use in populations displaced by
conflict”, Conflict and Health, vol. 5, No. 1 (2011).
of differential access to basic needs such as adequate
nutrition, quality housing and schools, as well as
increased exposure to environmental toxins and haz-
ards. Poor access to services and social support and
a lack of collective neighbourhood efficacy com-
pound the problem.
177, 178
Adding to the challenge
is the lack of effective coping strategies that often
characterize disadvantaged children. These problems
tend to be compounded in individuals with refugee
or immigrant status.
179
A range of substance use
177 Candice L. Odgers and others, “Supportive parenting
mediates widening neighborhood socioeconomic disparities
in children’s antisocial behavior from ages 5 to 12”,
Development and Psychopathology, vol. 24, No. 3 (2012), pp.
705–721.
178 Fay Saechao and others, “Stressors and barriers to using
mental health services among diverse groups of first-
generation immigrants to the United States”, Community
Mental Health Journal, vol. 48, No. 1 (2012), pp. 98–106.
179 India J. Ornelas and Krista M. Perreira, “The role of
migration in the development of depressive symptoms
Table 3
Summary of substance use stages and associated mental and physical health conditions,
by life
Source: T. M. Schulte and Y. Hser, “Substance use and associated health conditions throughout the lifespan”, Public Health
Review, vol. 35, No. 2 (2014).
Substance
Physical/medical
conditions
Mental health/
psychiatric disorders
Adolescence
Alcohol
Cannabis
Tobacco
Inhalants
Psychotherapeutic drugs
• Amphetamines
• Opioids/pain relievers
Accidental injury
• Automobile
• Accidents
Physical/sexual violence
Poisoning/overdose
Sexually transmitted diseases
Respiratory problems
• Asthma
Pain-related diagnoses
Suicidal ideation/behaviours
Internalizing disorders
• Depression
• Anxiety
Externalizing disorders
• Oppositional defiant disorder
• Attention deficit/hyperactivity disorder
• Conduct disorder
Adulthood
Alcohol
Cannabis
Tobacco
Psychotherapeutic drugs
• Opioids/pain relievers
• Tranquillizers/benzodiazepines
Cocaine/”crack”
Heroin
Methamphetamine
Poisoning/overdose
Sexually transmitted diseases
Cancers
Heart disease/hypertension/stroke
Reproductive morbidity/fetal damage
Diabetes
Respiratory problems
• Asthma
• Infection
Liver damage/disease
Suicidal ideation/behaviours
Mood disorders
• Depression
• Bipolar I and II
Anxiety disorders
• Panic disorder
• Post-traumatic stress disorder
• Social and specific phobias
• Generalized anxiety disorder
Antisocial personality disorder
Older Adulthood
Alcohol
Psychotherapeutic drugs
• Opioids/pain relievers
• Sedatives/benzodiazepines
• Amphetamines
Cannabis
Tobacco
Accidental injury
Cirrhosis
Heart attack/stroke
Insomnia
Cancers
Diabetes
Suicidal ideation/behaviours
Depression/bereavement
Anxiety disorders
• Social and specific phobias
• Generalized anxiety disorder
Dementia/Wernicke-Korsakoff Syndrome
Insomnia
DRUGS AND AGE B. Drugs and young people
37
4
Although many of these health problems are clearly
a result of substance use, other problems, such as
cognitive deficits and mental health disorders in
chronic users, may have preceded substance use,
even though they are often referred to as conse-
quences. Disentangling the antecedents from the
consequences of substance use represents one of the
most fundamental challenges in the field, with the
greatest implications for prevention of substance use
in adolescence.
Nevertheless, substance use among teenagers, in
particular young teenagers, is of particular concern
given the evidence that substances with psychoac-
tive effects have a greater impact on adolescents than
adults.
184
Age-related variations in drug responses
are likely to be the result of differences in the phar-
macological effects of substances on the brain
systems, such as the mesolimbic dopamine system,
that are still under construction. These differences
may have significant implications for adolescents
who exhibit reduced sensitivity to various
substance use disorders: clinical, functional, and family
relationship correlates”, Psychosis, vol. 4, No. 1 (2012), pp.
52–62.
184 Nicole L. Schramm-Sapyta and others, “Are adolescents
more vulnerable to drug addiction than adults? Evidence
from animal models”, Psychopharmacology, vol. 206, No. 1
(2009), pp. 1–21.
is associated with deficits in domains including phys-
ical health, cognitive functioning, educational
achievement and psychology, as well as overall
impairment in social competencies and relation-
ships.
181
Physical health problems experienced by
young drug users most obviously include increased
risk of overdose, accidental injury such as motor
vehicle accidents or falls, and attempted suicide. A
large, national study of 856,385 people who were
admitted for drug use disorders into publicly funded
treatment facilities in the United States showed that
28 per cent of the respondents had psychiatric
comorbidity.
182
Regular substance use can also pro-
foundly impact neurodevelopment, which can
interfere with academic performance and cognitive
functioning during adolescence and lead to dysfunc-
tion in the social and employment realms later in
life.
183
181 Robert J. Johnson and Howard B. Kaplan, “Stability
of psychological symptoms: drug use consequences
and intervening processes”, Journal of Health and Social
Behavior, vol. 31, No. 3 (1990), pp. 277–291.
182 Noa Krawczyk and others, “The association of psychiatric
comorbidity with treatment completion among clients
admitted to substance use treatment programs in a U.S.
national sample”. Drug and Alcohol Dependence, vol. 175
(June 2017), pp. 157–163.
183 Kim T. Mueser and others, “Antisocial personality disorder
in people with co-occurring severe mental illness and
THE NEGATIVE HEALTH EFFECTS OF CANNABIS
LONG-TERM/HEAVY USESHORT- TERM EFFECTS
Altered brain
development
Increased risk of chronic
psychosis disorders
(including schizophrenia)
Cognitive impairment, with
lower IQ among those who
were frequent users
during teen years
Symptoms of
chronic bronchitis
Less life satisfaction
and achievement
Poor educational outcome,
with increased likelihood of
dropping out of school
In high doses:
paranoia and
psychosis
Impaired
short-term
memory
Impaired
motor
coordination
STDs
Altered judgement,
increased risk in sexual
behaviour that causes
transmission of STDS
?
?
?
IQ
%
Source: Nora D. Volkow and others, “Adverse health effects of marijuana use”, New England Journal of Medicine, 370(23)
(2014), pp. 2219–2227.
38
WORLD DRUG REPORT 2018
use in adolescence, particularly when continued into
adulthood.
189, 190
Harmful use of substances
influences all the people in an individual’s life, as
well as society more broadly through the associated
costs of their social, physical and mental health
problems.
191
The cumulative and interactive
consequences of harmful drug use further undermine
young people’s socioeconomic standing, the quality
of the parenting they provide, their ability to develop
positively supportive relationships and their ability
to maintain employment, which further reinforces
their substance use.
192
Consequences for children and
adolescents of substance use by caregivers
Children and adolescents whose caregivers have sub
-
stance use disorders are significantly compromised
in terms of their safety, mental and physical health,
and school readiness.
193, 194
They can be directly
exposed to dangerous substances, and the ability of
caregivers to adequately supervise and nurture their
development can be compromised as a result of drug
use disorders. Children affected by the harmful use
of substances by their parents exhibit higher levels
of externalizing symptoms such as attention-deficit
hyperactivity disorder or antisocial personality dis-
order and of internalizing symptoms such as
depression, anxiety or post-traumatic stress disorder,
which are key risk factors for adverse developmental
trajectories.
195
As they approach adolescence, chil-
189 Dieter Henkel, “Unemployment and substance use: a
review of the literature (1990–2010)”, Current Drug Abuse
Reviews, vol. 4, No. 1 (2011), pp. 4–27.
190 WHO, Health for the world’s adolescents: a second chance
in the second decade. Available at http://apps.who.int/
adolescent/second-decade.
191 Steve Sussman, Silvana Skara and Susan L. Ames,
“Substance abuse among adolescents”, Substance Use and
Misuse, vol. 43, Nos. 12 and 13 (2008), pp. 1802–1828.
192 “Comorbidity: addiction and other mental illnesses”.
193 Sonja Bröning and others, “Selective prevention
programs for children from substance-affected families:
a comprehensive systematic review”, Substance Abuse
Treatment, Prevention, and Policy, vol. 7, No. 23 (2012).
194 Center for Children’s Justice, “Pennsylvania’s heroin and
opioid ‘epidemic’ jeopardizes early childhood”, Children’s
justice and advocacy report, 2016. Available at www.c4cj.
org.
195 Ricardo Velleman and Lorna Templeton, “Understanding
and modifying the impact of parents’ substance misuse on
children”, Advances in Psychiatric Treatment, vol. 13, No. 2
(2007), pp. 79–89.
substances, increasing the tendency to consume
greater amounts and more drug types, thereby com-
promising their neurodevelopment.
185
Although there have been claims that chronic sub-
stance use may permanently damage the brain, the
evidence from human studies is equivocal.
186
This
inconclusiveness may be due in part to the meth-
odologies that have been employed to assess the
possible developmental consequences of substance
use. Nevertheless, the literature suggests that there
may be a dose-response relationship between sub-
stance use and cognitive deficits, providing some
support for substance-induced alterations, in par-
ticular in memory, attention and executive
functions.
187
Studies that have included individuals
who initiate substance use during adolescence show
persistent deficits into adulthood, with reported
cognitive decline 10 years later, even in those who
had quit, but more so for those who continued to
use drugs.
188
Of increasingly greater concern is that the use of
multiple substances — polysubstance use — is wide-
spread and represents a major challenge to prevention
and treatment efforts. Polydrug use confers greater
health risks and negative consequences, as well as
poorer outcomes of interventions among users.
The direct effects of harmful substance use on the
adolescent brain dynamically interact with the social
and environmental contexts to which users are
exposed, increasing the risk of poor outcomes in
numerous functional domains. Unemployment,
physical health problems, dysfunctional social
relationships, susceptibility to accidents, suicidal
tendencies and behaviours, mental illness and even
lower life expectancy are all increased by substance
185 Ibid.
186 Nadia Solowij and Robert Battisti, “The chronic effects of
cannabis on memory in humans: a review”, Current Drug
Abuse Reviews, vol. 1, No. 1 (2008), pp. 81–98.
187 Thomas Lundqvist, “Cognitive consequences of cannabis
use: comparison with abuse of stimulants and heroin with
regard to attention, memory and executive functions”,
Pharmacology Biochemistry and Behavior, vol. 81, No. 2
(2005), pp. 319–330.
188 Karel L. Hanson and others, “Impact of adolescent
alcohol and drug use on neuropsychological functioning
in young adulthood: 10–year outcomes”, Journal of Child
and Adolescent Substance Abuse, vol. 20, No. 2 (2011), pp.
135–154.
DRUGS AND AGE B. Drugs and young people
39
4
Another interrelated factor is the co-occurrence of
mental health disorders in individuals who have a
substance use disorder, which further hinders the
ability of caregivers to adequately parent and provide
support for healthy child development.
205, 206
Such
situations have repeatedly been shown to be a strong
predictor of substance use in adolescence among the
children of affected individuals.
207, 208
Further compounding the problem is the high preva-
lence of maltreatment, poverty, community violence
and substandard housing conditions experienced by
children whose caregivers suffer from drug use dis-
orders, although this scenario is not universal.
209
The psychological trauma of exposure to such con-
ditions has as profound an impact as the harm to
the physical health of children of individuals who
have substance use disorders. The most frequent
and long-term addiction-related mental and behav-
ioural health problems developed by children
include post-traumatic stress disorder, depression,
anxiety, externalizing behaviours such as aggression,
harmful use of substances and many other maladap-
tive reactions.
Another common feature of harmful use of sub-
stances by parents is prenatal exposure to substances,
which is considered as both a direct and a mediating
mechanism. Prenatal and early exposure to cigarette
smoke has been shown to increase children’s pro-
pensity to smoke, become dependent on nicotine
and exhibit externalizing behaviours, such as con-
duct problems (e.g., aggression), and internalizing
205 Kimberlie Dean and others, “Full spectrum of psychiatric
outcomes among offspring with parental history of mental
disorder”, Archives of General Psychiatry, vol. 67, No. 8
(2010), pp. 822–829.
206 Kathleen R. Merikangas, Lisa C. Dierker and Peter
Szatmari, “Psychopathology among offspring of parents
with substance abuse and/or anxiety disorders: a high-risk
study”, Journal of Child Psychology and Psychiatry, vol. 39,
No. 5 (2003), pp. 711–720.
207 S. N. Madu and M. P. Matla, “Correlations for perceived
family environmental factors with substance use among
adolescents in South Africa, Psychological Reports, vol. 92,
No. 2 (2003), pp. 403–415.
208 D. De Micheli and M. L. Formigoni, “Are reasons for the
first use of drugs and family circumstances predictors of
future use patterns?”, Addictive Behaviors, vol. 27, No. 1
(2002), pp. 87–100.
209 Child Welfare Information Gateway, “Parental substance
use and the child welfare system”, Bulletins for Professionals
Series (October 2014). Available at www.childwelfare.gov.
dren exposed to a caregiver’s harmful substance use
more often exhibit early onset of substance use
themselves,
196, 197
earlier episodes of drunkenness,
198
more binge drinking
199
and a much greater likeli-
hood of developing substance use disorders at a
younger age than their counterparts.
200
In effect,
exposure to a caregiver’s harmful substance use places
children’s ability to meet developmental milestones
in jeopardy. They face a significantly heightened
risk of academic failure, severe behavioural and
mental health problems, criminality and inability
to enter the workforce.
201, 202, 203
In part, the relationship between harmful use of
substances by a parent and the substance use out-
comes of a child are mediated by parental neglect,
204
which biases the developmental trajectory toward
these outcomes. The risk is transmitted through
both the direct effects of neglectful and poor par-
enting and prevailing living circumstances, such as
unsupportive interpersonal relationships and disor-
ganized households.
196 Geary S. Alford, Ernest N. Jouriles and Sara C. Jackson,
“Differences and similarities in the development of drinking
behavior between alcoholic offspring of alcoholics and
alcoholic offspring of nonalcoholics”, Addictive Behavior,
vol. 16, No. 5 (1991), pp. 341–347.
197 Emily F. Rothman and others, “Adverse childhood
experiences predict earlier age of drinking onset: results
from a representative US sample of current or former
drinkers”, Pediatrics, vol. 122, No. 2 (2008), pp. 298–304.
198 Thomas McKenna and Roy Pickens, “Alcoholic children of
alcoholics”, Journal of Studies on Alcohol and Drugs, vol. 42,
No. 11 (1981), pp. 1021–1029.
199 Elissa R. Weitzman and Henry Wechsler, “Alcohol use,
abuse and related problems among children of problem
drinkers: findings from a national survey of college alcohol
use”, Journal of Nervous and Mental Disease, vol. 188, No. 3
(2000), pp. 148–154.
200 Andrea Hussong, Daniel Bauer and Laurie Chassin,
“Telescoped trajectories from alcohol initiation to disorder
in children of alcoholic parents”, Journal of Abnormal
Psychology, vol. 117, No. 3 (2008), pp. 63–78.
201 Dennis C. Daley, “Family and social aspects of substance
use disorders and treatment”, Journal of Food and Drug
Analysis, vol. 21, No. 4 (2013), pp. S73–S76.
202 Jeanne Whalen, “The children of the opioid crisis”, Wall
Street Journal, updated 15 December 2006.
203 Chris Elkin, “Born to do drugs: overcoming a family his-
tory of addiction”, 10 February 2016. Available at www.
drugrehab.com.
204 Marija G. Dunn and others, “Origins and consequences
of child neglect in substance abuse families”, Clinical
Psychology Review, vol. 22, No. 7 (2002), pp. 1063–1090.
40
WORLD DRUG REPORT 2018
Young people and the supply chain
Young people can be affected not only by drug use
but also by illicit crop cultivation, drug production
and trafficking in drugs. Exposure to these different
activities can have equally long-term implications
for young people and their future prospects. Some
of these activities are discussed in the present
subsection.
Illicit crop cultivation and drug
manufacture
Opium poppy cultivation
Afghanistan continues to be the world’s largest
opium producer, where insurgent groups such as
the Taliban have been able to generate significant
revenue by taxing drugs passing through the regions
they control.
215
Media outlets have reported that
independent young farmers witnessing the lucrative
business have also attempted to participate in this
“profitable trade”.
216
Boys as young as 6 work in
the fields, harvesting the opium poppy and collecting
the opium that will be used to produce heroin. Some
cases have been reported of farmers who, unable to
pay back loans taken to cultivate opium, turn to
arranged child marriage. In such cases, families offer
their daughters to be married, often to older men
or to live far away from the support network they
grew up with, as payment or simply because they
can no longer support them financially.
217
In Myanmar, some 1.3 million children under the
age of 14 are thought to be child labourers, accord-
ing to statistics from the Ministry of Labour,
Immigration and Population and reported in the
215 United States, Department of State, International Narcotics
Control Strategy Report 2017, vol. I, Drug and Chemical
Control, (Washington D.C., March 2017), pp. 90–91.
216 Franz J. Marty, “Afghanistan’s Opium Trade: A Free Market
of Racketeers”, The Diplomat, 19 July 2017.
217 Fariba Nawa, Opium Nation: Child Brides, Drug Lords,
and One Woman’s Journey Through Afghanistan, (New York,
Harper Perennial, 2011).
symptoms, such as depression and anxiety.
210, 211
Prenatal drug and alcohol exposure are associated
with subsequent behavioural problems in childhood
and adolescence, including eventual substance use
and harmful use of substances.
212, 213
Alterations
associated with self-regulation, reward and motiva-
tion in the neurological systems of a fetus, caused
by the properties of the substance or substances used
by pregnant women, appear to be how prenatal sub-
stance exposure affects children. The effects of these
sorts of prenatal exposure on mental health and
behaviour will tend to exacerbate any pre-existing
susceptibilities to substance use and to developing
substance use disorders.
Understanding differential pathways
to substance use and implications for
prevention and policy
It is well known that individuals who experience
adversity as children have a higher risk of develop-
ing drug use disorders as adults.
214
The current
misconception that individuals are equally vulner-
able to substance use and harmful use ignores the
scientific evidence that has consistently shown indi-
vidual differences in propensity. These widespread
beliefs hinder the application of effective and tar-
geted solutions. The multiple life-course conditions
that influence whether an individual will develop a
serious problem with substances are alterable and,
in many cases, preventable. Protective conditions
can be strengthened, while detrimental factors can
be attenuated or even prevented.
210 Marie D. Cornelius and others, “Long-term effects of
prenatal cigarette smoke exposure on behavior dysregulation
among 14-year-old offspring of teenage mothers”, Maternal
and Child Health Journal, vol. 16, No. 3 (2012), pp. 694–
705.
211 Brian J. Piper and Selena M. Corbett, “Executive function
profile in the offspring of women that smoked during
pregnancy”, Nicotine and Tobacco Research, vol. 14, No. 2
(2012), pp. 191–199.
212 Jennifer A. DiNieri and others, “Maternal cannabis use
alters ventral striatal dopamine D2 gene regulation in the
offspring”, Biological Psychiatry, vol. 70, No. 8 (2011), pp.
763–769.
213 Thitinart Sithisarn, Don T. Grangerand and Henrietta
S. Bada, “Consequences of prenatal substance use”,
International Journal of Adolescent Medicine and Health, vol.
24, No. 2 (2011), pp. 105–112.
214 Diana H. Fishbein and Ty A. Ridenour, “Advancing
transdisciplinary translation for prevention of high-risk
behaviors: introduction to the special issue”, Prevention
Science, vol. 14, No. 3 (2013), pp. 201–215.
Information on the involvement of young people
in the drug supply chain is limited and, in most
instances, is restricted to media reports. Conse-
quently, media sources, in addition to other reports,
have been used to highlight issues on young people
in place of evidence purely from research.
DRUGS AND AGE B. Drugs and young people
41
4
media.
218
Some of the reported occupations of child
labourers include drug production and trafficking.
A ripple effect on the education of these children is
likely, as parents usually consider a basic level of
literacy and numeracy to be sufficient.
219
Within the last decade, drug cartels and organized
crime groups in Mexico have increasingly displaced
indigenous people not only from their land but also
from their community networks.
220
Many reports
have noted that children and young people in cer-
tain areas were being kidnapped and forced to work
in opium poppy cultivation, production and traf-
ficking by organized crime groups.
221, 222, 223
Coca bush cultivation
In Colombia, children between 6 and 13 who lived
in places affected by the armed conflict in coca
regions were often used as labour in the fields. At
the beginning of the 2010s, it was estimated that
there were about 18,000 children and teenagers in
illegal armed groups in Colombia and at least
100,000 in sectors of the illegal economy directly
controlled by those groups.
224
Most of those young
people were recruited before the age of 12, were
affected by poverty and came from regions affected
by violence. Some of those children grew up work-
ing with their parents in the coca harvest and in
coca paste distribution.
225
A significant number of teenage and young work-
ers, called raspachines, are responsible for coca leaf
collection in Bolivia (Plurinational State of), Colom-
bia and Peru. Young people from the Andean region,
218 Hoogan, “Too young to toil”.
219 Ibid.
220 Alejandra S. Inzunza and José Luis Pardo, “Cartels are
displacing an indigenous group that’s lived in this Mexican
state for centuries”, Vice News, 20 May 2016.
221 Convention on the Rights of the Child, Concluding
observations on the combined fourth and fifth periodic reports
of Mexico, CRC/C?MEX/CO/4.5
222 Mexico, Gaceta Parlamentaria, año XVI, número 3757-IX,
jueves 25 de abril de 2013.
223 Inter-American Commission on Human Rights, Situation
of human rights in Mexico, Organization of American States,
December 2015.
224 Natalia Springer, Como corderos entre lobos: del uso y
reclutamiento de niñas, niños y adolescentes en el marco del
conflicto armado y la criminalidad en Colombia (Bogotá,
Springer Consulting Services, 2012), pp. 20–30.
225 Ibid.
many of them indigenous, leave their families and
communities to find food, clothing, transportation
and entertainment. Wages in coca leaf collection are
substantially higher than the average for agricultural
work. Many of them are children of landless peas-
ants and lack the education and opportunities that
would normally allow them greater stability and
socioeconomic development. These young people
are the weakest link in the chain formed by the agro-
industrial system of coca. Given that juveniles are
unlikely to be held accountable for their crimes,
they are increasingly exposed to high-risk work such
as buying and transporting coca paste.
226, 227
Cannabis farms
Research on youth involvement in cannabis cultiva
-
tion is limited and concentrated in a few Western
countries. Given that cannabis is cultivated in vir-
tually every country, this evidence may mask
different global patterns. In Canada, Ireland and
the United Kingdom, the number of cannabis-grow-
ing operations, known as grow-ops, has increased
considerably in the past few years.
228, 229, 230
Media
outlets have reported that young people in the
United Kingdom, mostly trafficked from countries
in Asia, are recruited to work for the criminal organi-
zations running these farms.
231
They are often
locked up alone and forced to tend plants in con-
verted houses, usually in extremely dangerous
conditions. Among the risks mentioned are injury
or even death from dangerous equipment, fire, res-
piratory illness from mould, electrocution and
violence due to burglaries and turf wars between the
organizations running the grow-ops.
226 Juan G. Ferro and others, Jóvenes, coca y amapola: un estudio
sobre las transformaciones socioculturales en zonas de cultivos
ilícitos (Bogotá, Universidad Javeriana, 1999), p. 20.
227 Colombia, Programa Nacional Integral de Sustitución de
Cultivos Ilícitos, decree No. 896 of 29 May 2017.
228 Sue Reed, “Vietnamese child slaves working in UK cannabis
factories”, Daily Mail, 17 December 2017.
229 Migrant Rights Centre Ireland, “Trafficking for forced
labour in cannabis production: the case of Ireland” (Dublin,
2015).
230 Susan C. Boyd and Connie I. Carter, Killer Weed:
Marijuana Grow Ops, Media and Justice (Toronto, Canada,
University of Toronto Press, 2014), pp. 167–180.
231 Reed, “Vietnamese child slaves working in UK cannabis
factories”.
42
WORLD DRUG REPORT 2018
at these sites, visit them or are present during drug
manufacture may run acute health and safety
risks.
238
The age-related behaviours of young chil-
dren, such as frequent hand-to-mouth contact and
physical contact with their environment, increase
the likelihood that they will inhale, absorb or ingest
toxic chemicals, drugs or contaminated food.
239
In Australia, crystalline methamphetamine is manu-
factured and distributed by local motorcycle gangs
that work with major organized crime groups. These
groups often recruit children aged between 11 and
15 to cook the substance and target potential young
users in country towns.
240
Between 2006 and 2010
in New Zealand, police found 384 children in 199
laboratories, and convictions for neglect or abuse
were obtained for people in 19 laboratories. In those
cases, drug paraphernalia was stored in children’s
lunch boxes and drinking bottles.
241
Since 2012,
the number of minors, with an average age of 6
years, found in methamphetamine laboratories in
New Zealand has increased, according to the
National Drug Intelligence Bureau.
242
Young people in the drug trafficking
chain
Young people can become entangled in drug traf-
ficking in both the local and international drug
markets. However, the available evidence regarding
young people’s involvement in drug trafficking is
limited to a few countries and comes from a limited
number of studies.
At times, young people’s place of birth, as well as
their socioeconomic environment, determines how
they evolve inside criminal organizations. Beyond
exploitation, there are several reasons why a young
person may participate in drug dealing and traffick-
ing. They may do so as an aspirational financial
238 Ibid.
239 Karen Swetlow, “Children at clandestine methamphetamine
labs: helping meth’s youngest victims”, OVC Bulletin June
2003 (United States Department of Justice, Office of Justice
Programs, Office for Victims of Crime).
240 Caro Meldrum-Hanna, “Crystal meth: former drug lab
cook recruited at age 11 as outlaw motorbike gangs push
drugs in rural towns”, Four Corners, 20 October 2014.
241 “Children raised in meth labs”, New Zealand Herald, 2 June
2013.
242 New Zealand Police Association, “Meth Kids”, (2013) vol.
46, No.2. Available at https://www.policeassn.org.nz/news-
room/publications/featured-articles/meth-kids.
Media outlets have also reported that immigrants
often enter the United Kingdom with no intention
of cultivating cannabis. However, commercial can-
nabis cultivation offers itself as the obvious choice
for immigrants to pay back large debts to lenders
who threaten their families back home.
232
When
cannabis farms are raided, these youth workers may
be prosecuted, convicted and eventually imprisoned
for crimes they may have been forced to commit,
while their traffickers may evade justice.
233
Manufacture of synthetic drugs
Europe remains the most dynamic market for
synthetic drugs such as MDMA, amphetamine and,
to a lesser extent, methamphetamine, and organized
crime groups in the region are involved in the
manufacture of those drugs.
234
In Europe, the
number of home-based laboratories operated by
criminal groups has increased in the last decade, in
particular those for the production of
methamphetamine in Czechia and for MDMA in
the Netherlands.
235
In Asia, criminal syndicates
capitalize on the limited capacity of law enforcement
to police drug manufacturing, which exposes local
communities to the illegal drug industry. Inevitably,
children and young people within those communities
become involved in the production and supply chain
of drugs.
236
In the United States, most of the domestic labora-
tories seized in 2016 were small-capacity covert
production laboratories known as “one-pots” or
manufacturing sites known as “shake and bakes”.
They can be set up anywhere: in private residences,
motel and hotel rooms, trailers, campgrounds and
commercial establishments.
237
Children who live
232 Amelia Gentleman, “Trafficked and enslaved: the teenag-
ers tending UK cannabis farms”, The Guardian, 25 March
2017.
233 “Trafficking for forced labour in cannabis production”.
234 Europol, “Business fundamentals: how illegal drugs sustain
organised crime in the EU” (2017).
235 EMCDDA, European Drug Report 2017: Trends and
Developments, (Luxembourg, Publications Office of the
European Union, 2017).
236 Fifa Rahman and Nick Crofts, eds., Drug Law Reform
in East and Southeast Asia (Plymouth, United Kingdom,
Lexington Books, 2013), pp. 157–159.
237 United States,
Department of Justice, Drug Enforcement
Administration, 2017 National Drug Threat Assessment
(Washington, D.C., 2017).
DRUGS AND AGE B. Drugs and young people
43
4
radar. Informal groups known as “county lines”,
which are not necessarily affiliated as gangs, have
been shown to supply drugs from an urban hub to
local markets in the United Kingdom.
247
Such a
phenomenon includes the forced recruitment of
young people, many aged between 13 and 18, who
may have accumulated drug debts. Most recruits
work in remote areas for these groups as street deal-
ers or runners, or by arranging accommodation,
hiring cars or booking train tickets, among other
minor activities. In this manner, the group exploits
young or vulnerable people to achieve the storage
or supply of drugs, movement of cash proceeds and
to secure the use of dwellings. Group leaders or
individuals exploited by them regularly travel
between the urban hub and the county market to
replenish stock and deliver cash.
Victims may not wish to continue working for
county lines, but are afraid of self-incrimination or
retribution. They are exposed to varying levels of
exploitation, including physical, mental and sexual
harm, sometimes over protracted periods. Some vul-
nerable individuals are also trafficked into remote
markets to work and others have their homes taken
over (a process known as being “cuckooed”) through
force or coercion. Many children are also lured by
the promise of earnings and valuable assets. The use
of social media to recruit members is also reported,
and young women are often involved in recruiting
other young women who may be vulnerable and in
crisis.
248
Drug dealing in local markets in violent
contexts
In local contexts where violence prevails, drug
markets may directly harm all actors involved in
drug-related activities, including young people.
249
In Brazil, teenagers and young adults who work
within drug supply networks are often looking for
excitement and a means to identify with local groups
or gangs. They also want to consume the illegal
drugs that they sell or traffic. Officials tend to ascribe
247 United Kingdom, National Crime Agency, “County lines
violence, exploitation and drug supply 2017: national
briefing report” (November 2017).
248 Ibid.
249 Thomas Babor and others, Drug Policy and the Public Good
(Oxford, Oxford University Press, 2010).
measure or as part of their family’s established eco-
nomic activities. In other cases, socioeconomic
disadvantage is thought to place young people at
increased risk of drug dealing in order to survive in
an environment of limited opportunities.
243
Most
studies in the United States identify participants
who deal drugs as a means to seek economic gain
to supplement meagre wages. Young people are also
involved in the illicit drug trade to obtain easy access
to drugs or because of parental drug use or dealing.
Carrying or accessing guns has also been identified
as a variable that could lead adolescents to drug
dealing.
244
Although the definition of minors and
juveniles differs across countries, minors and juve-
niles are subject to lenient laws, prosecution and
penalties for criminal offences (compared with
adults), including drug offences, which makes it
convenient for organized crime groups to exploit
young people to undertake various tasks within the
drug supply chain.
Drug dealing in local markets that are
non-violent or have a low level of violence
In many places, local-level drug transactions tend
to occur in contexts that have a low level of violence
or that are non-violent. For example, in Estonia, the
most widespread reasons for children becoming
involved in drug dealing include the influence of
close friends and peers, the desire to become rich,
a lack of an alternate income and the need for free
drugs.
245
In the United Kingdom, the number of
children under the age of 16 arrested on suspicion
of supplying “crack” cocaine, heroin or cocaine has
been increasing in recent years.
246
Drug traffickers
perceive children as cheap, expendable, easily con-
trolled and often able to operate under the police’s
243 Leah J Floyd and others, “Adolescent drug dealing and
race/ethnicity: a population-based study of the differential
Impact of substance use on involvement in drug trade”,
American Journal of Drug and Alcohol Abuse, vol 36, No.2
(2010), pp.87–91.
244 Tatiana Starr Daniels, “What influences some black males
to sell drugs during their adolescence”, McNair Scholars
Journal, vol. 13, (Sacramento, California State University,
2012), pp. 21–39.
245 Nelli Kalikova, Aljona Kurbatova and Ave Talu, Estonia
Children and Adolescents Involved in Drug Use and
Trafficking: A Rapid Assessment, (Geneva, International
Labour Organization, International Programme on the
Elimination of Child Labour, 2002).
246 Adam Lusher, “Gangs recruiting children as young as 12 as
class A drug dealers”, The Independent, 14 July 2017.
44
WORLD DRUG REPORT 2018
structural factors that are exacerbated by a lack of
financial resources or frail family structures to chil-
dren’s attraction to gangs and drug trafficking.
250
Organized crime groups and gangs prefer to recruit
children and young adults for drug trafficking for
two reasons. The first is the recklessness associated
with this age group, even when they are faced with
police or rival gangs, and the second is their obedi-
ence in carrying out orders. The desire to belong to
a gang and to be highly regarded by its members
imparts to the children a sense of obedience and a
strong will to obey orders from and the rules of their
gang.
251
In Argentina, the selling of drugs in
deprived areas is done by a method known as men-
udeo, by which drugs are dispensed from bunkers
(small windowless buildings) staffed by a gang
member, often a teenager, or even a child. Often,
an armed soldado (guard) is on the payroll of the
local trafficker guards the area.
252
International markets
Young people involved in the illicit drug trade in
international markets are often part of large organ-
ized crime groups. They are used in different ways
for smuggling illegal substances across borders. In
the United States, gangs target young people who
can legally cross international borders,
253
while in
Peru, mochileros (backpackers) travel with illicit
cargo of cocaine to secret stash points.
254
Drug
bosses usually use children as lookouts at control
points or border check posts.
On the United States-Mexico border, many young
people are involved in drug trafficking, serving as
so-called “mules”, to carry drugs across the border.
Trafficking groups target young people who can
250 Jailson de Souza e Silva and André Urani, Brazil Children
in Drug Trafficking: A Rapid Assessment, Investigating the
Worst Form of Child Labour No. 20 (Geneva, International
Labour Organization, 2002).
251 Ibid.
252 Mauro Testa and Ross Eventon, “Vulnerable youth
and drug trafficking in Rosario, Argentina: between
stigmatisation and social control” (Swansea, United
Kingdom, Global Drug Policy Observatory, Swansea
University, February 2016).
253 Greg Moran, “There has been some progress, but youth
drug smuggling persists at the U.S-Mexico border”, Los
Angeles Times, 20 June 2016.
254 “A look at children’s role in cocaine production in Peru”,
published on YouTube by AJ+ on 7 May 2015.
legally cross the border because they are United
States citizens who may live in Tijuana and go to
school in the United States or possess a border cross-
ing card. In 2013, 118 young people were caught
smuggling cannabis, methamphetamine, heroin and
cocaine through the San Diego sector. By 2015, that
number had dropped to 70. This decline may be
attributed to several factors, including tighter border
security, but the numbers only reflect those who
were caught and not those who were successful in
crossing the border.
255, 256
The phenomenon of young people crossing borders
to smuggle drugs occurs in most regions of the
world. In Peru, media sources suggest that young
people help to transport cocaine from the valley of
three rivers — the Apurimac, Ene and Mantaro —
to secret stash points or clandestine airstrips, from
where the drugs are moved on by other means. Chil-
dren and teenagers are the principal workers in the
cocaine valley, where backpackers or mochileros walk
for more than 100 miles through the mountains to
avoid police checkpoints and armed gangs.
257
Although the journey is long and dangerous, the
payments make it lucrative, with every trip worth
about $2,000.
258
The mochileros are reportedly well
organized and prepared for attacks, either from rival
groups or the police.
Over the past five years, the number of ethnic
minority juveniles engaging in drug trafficking on
the border between the Lao People’s Democratic
Republic and Viet Nam has also increased, accord-
ing to media sources.
259
Suggestions were made that
about 20 young people smuggled drugs across the
border every day in 2017.
260
In recent decades, West Africa has emerged as a
major transit point for drug trafficking; according
to media sources, this has also increased the level of
255 Moran, “There has been some progress, but youth drug
smuggling persists at the U.S-Mexico border”.
256 “Mexico drug gangs using more children as ‘mules’”, CBS
News, 14 March 2012.
257 “A look at children’s role in cocaine production in Peru”.
258 Linda Presley, “The mochileros: high stakes in the high
Andes–the young backpackers risking their lives in cocaine
valley”, BBC News, 24 November 2015.
259 Juvenile drug traffickers multiply at Vietnam-Lao border”,
Voice of Vietnam, 27 October 2017.
260 Ibid.
DRUGS AND AGE B. Drugs and young people
45
4
durability over time, street-oriented lifestyle, youth-
fulness of members, involvement in illegal activities
and group identity.”
266
“Youthfulness” in this con-
text should be interpreted liberally, since a number
of studies indicate that most street gang members
appear to be adults.
267
Nonetheless, there is well-
266 UNODC, International Classification of Crime for Statistical
Purposes, version 1.0 (March 2015), p. 98.
267 For example, the National Youth Gang Survey in the
United States suggests that more than two thirds of urban
street gang members are adults. See National Gang Center,
National Youth Gang Survey Analysis, Demographics: age
of gang member. Available at www.nationalgangcenter.
exploitation of young people.
261
Media sources
reported that, in 2016, 158 young Nigerians were
awaiting execution for drug offences in China, Indo-
nesia, Malaysia and Singapore. Some had claimed
to be university students and were colluding with
drug traders to undermine the visa system and gain
entrance into Malaysia, Indonesia, Thailand or other
countries on drug trafficking routes.
262
What is the role of children and street
gang members in trafficking drugs?
Drug-related violence, street gangs and exploitation
of children by organized crime groups in the drug
trade are some of the main concerns of drug policies
all over the world. Using data from over 40 coun-
tries, about 3 per cent of people arrested or cautioned
for possession of drugs in 2015 were aged under
18).
263, 264
For more serious drug offences, such as
sales, only 1 per cent of those arrested or prosecuted
were children. Globally, children represent about
one third of the global population,
265
so children
are much less likely than adults to be arrested or
prosecuted for drug offences.
Nevertheless, this represents almost 70,000 children
arrested for drug possession and over 17,000 arrested
for serious drug offences in 2015. The share of chil-
dren among those arrested for drug offences varies
considerably between countries. In general, children
represent a larger share of those arrested for posses-
sion than for serious offences. Some countries report
that more than 10 per cent of people arrested for
drug possession are children, but most countries
report that fewer than 5 per cent of drug traffickers
are under 18.
Children may participate in drug markets through
an organized group, such as a street gang. The Inter-
national Classification of Crime for Statistical
Purposes defines a gang as “a group of persons that
is defined by a set of characteristics including
261 “Narcotics in Africa: an emerging drug market”, The
Economist (Nairobi), 14 April 2016.
262 Ismael Mudashir, “Drug trafficking: 158 Nigerians on death
row in China, Malaysia”, Daily Trust, 1 March 2016.
263 According to the United Nations Convention on the Rights
of the Child, adulthood starts at 18 years of age.
264 United Nations, Treaty Series, vol. 1577, No. 27531.
265 United Nations, Department of Economic and Social
Affairs, Population Division, World Population Prospects
2017. Available at https://esa.un.org/unpd/wpp.
Fig. 10
Proportion of people arrested or
cautioned for drug possession in 2015
who were under 18, selected countries
Source: UNODC, responses to the annual report questionnaire.
Fig. 11
Proportion of people arrested or cau-
tioned for serious drug offences in 2015
who were under 18, selected countries
Source: UNODC, responses to the annual report questionnaire.
Croatia
El Salvador
Germany
Honduras
Sweden
Switzerland
Canada
Bolivia (Plurina-
tional State of)
Russian Fed.
Zambia
Austria
Mexico
Australia
Kyrgyzstan
Philippines
Argentina
Morocco
Percentage
Madagascar
Mozambique
Austria
El Salvador
Honduras
Slovenia
Bolivia (Plurina-
tional State of)
Guatemala
Switzerland
Romania
Canada
Germany
Argentina
Ecuador
Hungary
Latvia
Brunei Darussalam
Philippines
Australia
Singapore
Dominican Rep.
30%
19%
15%
13%
12%
11%
11%
10%
9%
8%
7%
7%
6%
5%
3%
2%
2%
1%
1%
1%
1%
0%
5%
10%
15%
20%
25%
30%
35%
Madagascar
Austr ia
Honduras
Bolivia…
Switzerland
Canada
Argentina
Hungary
Brunei…
Austr alia
Dominican Rep.
Percentage
0%
5%
10%
15%
20%
25%
30%
35%
Madagascar
Austr ia
Honduras
Bolivia…
Switzerland
Canada
Argentina
Hungary
Brunei…
Austr alia
Dominican Rep.
0%
1%
2%
3%
4%
5%
6%
7%
8%
9%
Croatia
El Salvador
Germany
Honduras
Sweden
Switzerland
Canada
Bolivia…
Russian Fed.
Zambia
Austr ia
Mexico
Austr alia
Kyrgyzstan
Philippines
Argentina
Morocco
0%
1%
2%
3%
4%
5%
6%
7%
8%
9%
Croatia
El Salvador
Germany
Honduras
Sweden
Switzerland
Canada
Bolivia…
Russian Fed.
Zambia
Austr ia
Mexico
Austr alia
Kyrgyzstan
Philippines
Argentina
Morocco
46
WORLD DRUG REPORT 2018
Today, the most notorious street gangs are found in
Latin America, particularly the maras of the North-
ern Triangle of Central America. Children account
for a relatively high proportion of those arrested for
serious drug offences in Honduras and El Salvador
(6 per cent and 7 per cent, respectively).
271
Over
70 per cent of respondents to a survey of more than
1,000 gang members in El Salvador said they earned
less than $250 a month. Their primary source of
income appeared to be extortion,
272
so the role they
play in the drug economy appears to be
peripheral.
273
C. DRUGS AND OLDER
PEOPLE
The use of drugs among older people has long been
an under-researched area, the importance of which
has only recently become recognized. Changes in
global demographics point to an increase in both
the number and proportion of older people in all
regions. In this section, some of the concerns related
to the use of drugs among older people are briefly
in 2000 (William Rhodes and others, What America’s Users
Spend on Illegal Drugs, 1988–1998 (Washington, D.C.,
Office of National Drug Control Policy, 2000).
271 UNODC, responses to the annual report questionnaire.
272 International Crisis Group, “Mafia of the poor: gang
violence and extortion in Central America”, Latin America
Report No. 62 of 6 April 2017 (Brussels, 2017).
273 Cruz and others, The New Face of Street Gangs.
documented involvement of street gang members
who are children in the retailing of drugs.
Street gangs such as the Crips and the Bloods were
notorious for their role in selling “crack” cocaine in
parts of the United States from the late-1980s to
the mid-1990s. One study of more than 1,500
arrests for the sale of cocaine made between 1989
and 1991 in two Los Angeles suburbs found that
27 per cent involved gang members.
268
The 1996
United States National Youth Gang survey estimated
that 43 per cent of all street drug sales nationally
involved gang members.
269
Both “crack” cocaine
use and Los Angeles gang membership have declined
dramatically since that time.
270
gov/Survey-Analysis/Demographics#anchorage. Research
on street gangs in Trinidad and Tobago found that 87 per
cent of members were adults. See Charles Katz and David
Choate, “Diagnosing Trinidad and Tobago’s gang problem”,
conference paper presented at the annual meeting of the
American Society of Criminology, Los Angeles, California,
2010. A recent survey of gang members in El Salvador
found an average age of 25 years. See José Miguel Cruz and
others, The New Face of Street Gangs: The Gang Phenomenon
in El Salvador (2017).
268 Cheryl L. Maxson, “Street gangs and drug sales in two
suburban cities”, National Institute of Justice Research in
Brief Series (Washington D.C., July 1995).
269 Office of Juvenile Justice and Delinquency Prevention,
1996 National Youth Gang Survey (Washington D.C., July
1999).
270 According to online data from the Los Angeles Police
Department, the number of street gang members in the city
declined from over 64,000 in 1997 to 39,000 in 2005. The
number of “hardcore” cocaine users in the United States
declined from an estimated 1.1 million in 1988 to 445,000
Street gangs and drug trafficking
It has been alleged that street gang members, particularly
those involved in “mega-gangs” like Mara Salvatrucha,
are involved in international drug trafficking. Individual
gang members may move on to become drug traffick-
ers, of course, and the skills they acquire in gang activity
may prove useful in their new occupation. But there are
several reasons to be sceptical that international drug
trafficking is a primary activity of the street gangs them-
selves, or that street gangs are important in facilitating
international drug flows.
The territoriality of street gangs is often cited as one of
their defining characteristics. Not only does protecting
gang territory require time and attention, but also the
territories controlled tend to be located in slum areas,
far from the transportation corridors relevant to drug
trafficking. In the El Salvador gang survey, most of
the respondents were raised in poor communities and
dropped out of school before turning 16; many were
runaways. This lack of basic education and resources
makes it unlikely that they could compete in international
drug markets with sophisticated drug trafficking cartels.
Moreover, when asked about the nature of the groups
trafficking drugs in their countries, law enforcement
agencies from the Northern Triangle countries do not
mention street gangs.
Source: Max G. Manwaring, Street Gangs: The New Urban
Insurgency, (Carlisle, Pennsylvania, Strategic Studies Insti-
tute, United States Army War College, March 2005) ; John
P. Sullivan, “Transnational gangs: the impact of third gen-
eration gangs in Central America”, Air and Space Power
Journal, Second Trimester (2008). The definition used by
the United States Department of Justice, available at
www.justice.gov/criminal-ocgs/about-violent-gangs
47
DRUGS AND AGE C. Drugs and older people
4
explored, together with examples that illustrate the
particular issues and health consequences of drug
use among this group.
Changes in the extent of drug use
among older people
There is evidence in some countries that the use of
drugs among older people, although starting from
a low prevalence, has been increasing over the last
decade and at a faster rate than among younger age
groups.
In the United States, for example, data on the past-
year use of any drug shows that, between 1996 and
2016 there was hardly any change in the prevalence
rate among those aged 12–17, but drug use among
those aged 50 and above
274
rose from 1.3 per cent
to 9.8 per cent during that period, equivalent to a
more than sevenfold increase.
275
In terms of the
number of older drug users, the increase is even more
striking because of the growth in the population of
those aged 50 and above. The total number of people
in the United States who used drugs in the past year
at 50 and older rose from some 900,000 people in
1996 to 10.8 million people in 2016, equivalent to
a 12-fold increase.
The increase was particularly large during the period
2006–2016, when the total number of annual drug
users aged 50 and older tripled, from 3.6 to 10.8
million, and the annual prevalence rate of drug use
of those aged 50 and older more than doubled, from
4.1 to 9.8 per cent. For those aged 60 and above,
growth in prevalence rates was even more pro-
nounced, with an almost fourfold increase in the last
decade, while the total number of annual drug users
among those aged 60–64 quadrupled and increased
more than sixfold among those aged 65 and older.
In Germany, past-year use of any drug increased
more among those aged 40 and above than the
younger age groups in the period 2006–2015. Drug
use among those aged 18–24 showed a more modest
increase (22 per cent) over the same period.
274 Age 50 and above was the oldest age group category in the
1996 national household survey of the United States.
275 United States, Center for Behavioral Health Statistics and
Quality, 2016 National Survey on Drug Use and Health:
Detailed Tables (Rockville, Maryland, Substance Abuse and
Mental Health Services Administration, 2017 and previous
years).
Fig. 12
Annual prevalence of drug use and
changes in the United States of
America, by age, 2006 and 2016
Source: United States, Center for Behavioral Health Statistics
and Quality, 2016 National Survey on Drug Use and Health:
Detailed Tables (Rockville, Maryland, Substance Abuse and
Mental Health Services Administration, 2016 and previous
years).
0
5
10
15
20
25
30
35
40
45
12 years
14 years
16 years
18 years
20 years
22 years
24 years
26–29 years
30–34 years
35–39 years
40–44 years
45–49 years
50–54 years
55–59 years
60–64 years
65+ years
Annual prevalence
(percentage)
2006
2016
Who constitutes "older" in the
context of drug use?
There is no consistently adopted lower age cut-off to categorize
who is considered an “older” drug user. The cut-off age varies
quite extensively across studies, starting from as low as 35.
a
More generally, however, studies in European countries have
used 40 as the lower cut-off, although some studies from the
United States of America have used 50.
b
Given this lack of an internationally accepted definition of
“older drug users”, the present section contains information
on the older age groups as available and provides, as far as pos-
sible, comprehensive age breakdowns of the available statistics.
a
April Shaw, Senior Drug Dependents and Care Structures: Scotland
and Glasgow Report (Glasgow, Scottish Drugs Forum, March
2009).
b
EMCDDA, Selected Issue 2010: Treatment and Care for Older
Drug Users (Luxembourg, 2010).
0
1
2
3
4
5
6
12 years
14 years
16 years
18 years
20 years
22 years
24 years
26–29 years
30–34 years
35–39 years
40–44 years
45–49 years
50–54 years
55–59 years
60–64 years
65+ years
Ratio of prevalence
(2016 compared with 2006)
Age/age group
Ratio of 1 indicates no change
48
WORLD DRUG REPORT 2018
The use of cannabis has also been on the rise among
those aged 55–64 in some of the most populated
countries in Western Europe. Annual prevalence
data from France, Germany, Italy, Spain and the
United Kingdom show that cannabis use among
those in that age group has been increasing at a
higher rate than any other age group. The increase
in past-year cannabis use among those aged 15–24
and 25–34 in those countries has been much less
pronounced and, in some cases, the prevalence has
declined.
In Australia, there was a small decline in the annual
prevalence rate of drug use for those aged 14–19
years during the period 2007–2016, but with preva-
lence rates increasing by 60 to 70 per cent in the
50–59 and 60 and older age groups.
Fig. 13
Annual prevalence of cannabis use and changes in selected countries in Western Europe,
by age group, selected years
Source: EMCDDA, Statistical Bulletin 2017.
Studies among older drug
users are limited
Drug use among older people is an under-researched
area, the importance of which has only recently
been recognized.
a, b
It should be noted that most
studies among older drug users were conducted in
developed countries, in particular the United States
of America and in countries in Europe, and therefore
the conclusions drawn from the literature may not
be generalizable to the rest of the world.
a
Matthew H. Taylor and George T. Grossberg, “The
growing problem of illicit substance abuse in the
elderly: a review”, Primary Care Companion for CNS
Disorders, vol. 14, No. 4 (2012).
b
Anne Marie Carew and Catherine Comiskey, “Treat-
ment for opioid use and outcomes in older adults:
a systematic literature review”, Drug and Alcohol
Dependence, vol. 182 (2018), pp. 48-57.
0
5
10
15
20
25
30
15–24 years
25–34 years
35–44 years
45–54 years
55–64 years
15–24 years
25–34 years
35–44 years
45–54 years
55–64 years
15–24 years
25–34 years
35–44 years
45–54 years
55–64 years
15–24 years
25–34 years
35–44 years
45–54 years
55–64 years
15–24 years
25–34 years
35–44 years
45–54 years
55–64 years
Germany
(2006, 2015)
Fran ce
(2005, 2014)
United Kingdom
(2006, 2015)
Italy
(2008, 2014)
Spain
(2006, 2015)
Annual prevalence (percentage)
0
1
2
3
4
5
6
15–24 years
25–34 years
35–44 years
45–54 years
55–64 years
15–24 years
25–34 years
35–44 years
45–54 years
55–64 years
15–24 years
25–34 years
35–44 years
45–54 years
55–64 years
15–24 years
25–34 years
35–44 years
45–54 years
55–64 years
15–24 years
25–34 years
35–44 years
45–54 years
55–64 years
Germany Fran ce United Kingdom Italy Spain
Ratio of prevalence (most recent
year compared with earliest year)
11
Ratio of 1 indicates no change
49
DRUGS AND AGE C. Drugs and older people
4
In Chile, the past-year use of cannabis among those
aged 45–64 showed a fourfold increase over the
decade to 2016, and an almost 30-fold increase
between 1996 and 2016. The rise in the annual
prevalence of cannabis use was less pronounced
among younger age groups. A similar pattern was
also revealed for the use of cocaine: the annual preva-
lence of use declined for those aged 12–18 and
19–25 during the period 1996–2016, but increased
14-fold among those aged 35–44.
What factors might lie behind the
increase in the extent of drug use?
There are a number of factors that could explain
the increased prevalence of drug use observed among
older people in some countries. Changing percep-
tions of the risks associated with drug use, the
increased availability of drugs, changes in social
acceptance of drug use and self-medication to deal
with pain or anxiety or challenges associated with
retirement might all contribute to the initiation or
resumption of drug use in older people. Another
factor could be a cohort effect, whereby groups of
people share common social and cultural experiences
because of when they were born. These experiences
might be different from those of previous cohorts.
The increase in drug use seen among the older popu-
lation could be a consequence of the ageing of a
cohort of users who have a higher prevalence of
substance use compared with previous cohorts.
There is evidence that, in western countries, the
baby-boom generation (born between 1946 and
1964), used drugs when they were young more than
the previous generation. Many of them have con-
tinued to use drugs into old age, and this is reflected
in the increasing prevalence of drug use seen among
Fig. 14
Annual prevalence of drug use and
changes in Germany, by age group,
2006–2015
Source: D. Piontek, E. Gomes de Matos, J. Atzendorf, and L.
Kraus, Kurzbericht Epidemiologischer Suchtsurvey: Trends
der Prävalenz des Konsums illegaler Drogen und des klinisch
relevanten Cannabisgebrauchs nach Geschlecht und Alter
1990-2015 (Munich, IFT Institut für Therapieforschung, 2016).
Fig. 15
Annual prevalence of drug use and
changes in Australia, by age group,
2007–2016
Source: Australian Institute of Health and Welfare, National
Drug Strategy Household Survey 2016: Detailed Findings,
Drug Statistics Series No. 31 (Canberra, September 2017).
0
5
10
15
20
25
18–24
years
25–39
years
40–59
years
60–64
years
Annual prevalence (percentage)
Age group
2006
2015
0
5
10
15
20
25
30
14–19
years
20–29
years
30–39
years
40–49
years
50–59
years
60 years
and
older
Annual prevalence (percentage)
Age group
2007
2016
0
0.5
1
1.5
2
2.5
3
18–24
years
25–39
years
40–59
years
60–64
years
Ratio of prevalence
(2015 compared with 2006)
Age group
Ratio of 1 indicates no change
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
14–19
years
20–29
years
30–39
years
40–49
years
50–59
years
60 years
and
older
Ratio of prevalence
(2016 compared with 2007)
Age group
Ratio of 1 indicates no change
50
WORLD DRUG REPORT 2018
reported higher rates of substance use compared
with the previous generation.
280, 281
Among those
aged 50–59, past-year use of cannabis increased from
3.1 per cent to 5.7 per cent from 2002 to 2007, and
the rate of past-year non-medical use of prescription
drugs increased from 2.2 per cent to 4.4 per cent.
Typical characteristics associated with continued
drug use in this age group included male gender,
unmarried status, early onset of drug use, lower
levels of education, low income, unemployment as
a result of disability, recent alcohol or tobacco use
and having a major depressive episode in the previ-
ous year. In addition to the cohort effect of continued
cannabis use by baby boomers, a change in the per-
ceptions around cannabis may also have contributed
to an increase in use. Over the past decade, decreas-
ing risk perceptions of harm and an ongoing debate
around legalization of the drug might have influ-
enced the use of cannabis.
282, 283, 284
Among countries in Europe with a higher prevalence
of cannabis use among older people, similar age
cohort effects have been identified to explain increas-
ing trends in the use of cannabis. Analyses of
historical data suggest that the main cause of the
phenomenon is an ageing cohort containing a
277 Roger Nicholas and others, Preventing and Reducing
Alcohol- and Other Drug-Related Harm among Older People:
A Practical Guide for Health and Welfare Professionals
(Adelaide, South Australia, National Centre for Education
and Training on Addiction, Flinders University, 2015).
278 Beth Han, Joseph Gfroerer and James Colliver, “An
examination of trends in illicit drug use among adults
aged 50 to 59 in the United States”, OAS Data Review
(Rockville, Maryland, Office of Applied Studies, Substance
Abuse and Mental Health Services Administration
(SAMHSA), August 2009).
279 Frederic C. Blow and Kristen L. Barry, “Alcohol and
substance misuse in older adults”, Current Psychiatry Reports,
vol. 14, No. 4 (2012), pp. 310–319.
280 Li-Tzy Wu and Dan G. Blazer, “Illicit and nonmedical drug
use among older adults: a review”, Journal of Ageing and
Health, vol. 23, No. 3 (2011), pp. 481–504.
281 Benjamin H. Han and others, “Demographic trends among
older cannabis users in the United States, 2006–13”,
Addiction, vol. 112, No. 3 (2010), pp. 516–525.
282 Han, Gfroerer and Colliver, “An examination of trends in
illicit drug use among adults aged 50 to 59 in the United
States”.
283 William C. Kerr, Camillia Lui and Yu Ye, “Trends and age,
period and cohort effects for marijuana use prevalence in
the 1984–2015 US National Alcohol Surveys”, Addiction,
vol. 113, No. 3 (2017), pp. 473–481.
284 World Drug Report 2017 (United Nations publication, Sales
No. E.16.XI.6).
older age groups in many developed countries as
this cohort ages.
276, 277, 278, 279
For instance, the United States has witnessed sig-
nificant increases in the past-year use of cannabis
among those aged 50 and older. This trend is cap-
turing, in part, the ageing baby boomers, who
276 Caryl M. Beynon, “Drug use and ageing: older people do
take drugs!”, Age and Ageing, vol. 38, No. 1 (2009), pp.
8–10.
Fig. 16
Changes in annual prevalence of drug
use in Chile, by age group, 1996–2016
Source: National Drug and Alcohol Prevention and Rehabilitation
Service (SENDA), Décimo Segundo Estudio Nacional de Drogas
en Población General de Chile, 2016 (Chilean Drug Observatory,
December 2017)
Note: The annual prevalence of cocaine use is reported at less than
0.1 per cent for 1996 among those aged 45–64 years. In calculating
the ratio, a prevalence of 0.1 per cent was used. Given the uncer-
tainty around this assumption and the possibility that the ratio might
be much higher, a cross-hatched bar is shown for the increase of
cocaine use among those aged 45–64 years over the period 1996–
2016.
0
5
10
15
20
25
30
35
40
12–18
years
19–25
years
26–34
years
35–44
years
45–64
years
Annual prevalence (percentage)
Age group
Cannabis
1996
1998-2014
2016
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
12–18
years
19–25
years
26–34
years
35–44
years
45–64
years
Annual prevalence (percentage)
Age group
Cocaine
1996
1998-2014
2016
0
5
10
15
20
25
30
12–18
years
19–25
years
26–34
years
35–44
years
45–64
years
Ratio of prevalence
(2016 compared with 1996)
Age group
Cannabis
Cocaine
Ratio of 1 indicates no change
51
DRUGS AND AGE C. Drugs and older people
4
than older retirees. This relationship was reversed
for those who deferred retirement and remained
employed at their primary workplaces. That is,
younger, retirement-eligible workers who deferred
retirement and continued to work reported fewer
drug-related problems than their older peers.
289
289 Samuel Bacharach and others, “Retirement and drug abuse:
the conditioning role of age and retirement trajectory”,
Addictive Behaviors, vol. 33, No. 12 (2008), pp. 1610–
1614.
sizeable proportion of individuals who continue
using drugs, almost exclusively cannabis, into an
advanced age.
285
Higher levels of drug use among older people might
also be explained by late initiation and changed
environmental conditions. However, adolescence
(12–17 years of age) is generally regarded as the
critical risk period for the initiation of substance
use.
286
In the United States, a study of drug users
aged 50–59 covering the period 2002–2007 found
that very few had started to use drugs at an older
age. Approximately 90 per cent had initiated drug
use by the age of 30 and about 72 per cent had
initiated non-medical use of prescription drugs by
that age. Only 3 per cent had initiated drug use and
9 per cent had initiated non-medical use of
prescription drugs at age 50 or older.
287
Reasons for
initiating drug use later in life included self-
medicating painful medical conditions. Older
people experience higher rates of mental health
conditions such as depression and higher rates of
social risk factors for drug use such as bereavement,
social isolation, financial problems and poor social
support.
288
A major life-changing event that occurs among older
people is retirement. Evidence on the impact of
retirement on drug use is very limited. However, a
study of 978 people in the United States looked at
various forms of retirement and the impact it has
on drug use. Being fully retired (that is, being com-
pletely disengaged from the workforce) was found
to be associated with increased use of drugs com-
pared with those who deferred retirement and
remained within the workforce. However, this
depended on the age of full retirement, with younger
retirees reporting more problems related to drug use
285 EMCDDA, Selected Issue 2010: Treatment and Care for
Older Drug Users (Luxembourg, Publications Office of the
European Union, 2010).
286 Substance Abuse and Mental Health Services Administra-
tion, Center for Behavioral Health Statistics and Quality.
“Age of substance use initiation among treatment admis-
sions aged 18 to 30”.
287 Han, Gfroerer and Colliver, “An examination of trends in
illicit drug use among adults aged 50 to 59 in the United
States”.
288 Matthew H. Taylor and George T. Grossberg, “The growing
problem of illicit substance abuse in the elderly: a review”,
Primary Care Companion for CNS Disorders, vol. 14, No. 4
(2012).
Fig. 17
Annual prevalence of cannabis use
and changes in the United States
of America and the European Union
among the general population and
those aged 55–64 years, 2006–2016
Source: United States, Department of Health and Human Ser-
vices, Substance Abuse and Mental Health Services Adminis-
tration, 2016 National Survey on Drug Use and Health, and
previous years; and EMCDDA, Statistical Bulletin 2017.
Note: Prevalence rates for the European Union are population-
weighted means of the national estimates. For years where a prev-
alence rate is not available for a country, these are either linearly
interpolated between the years where national rates are available
or, if this is not possible, given the same rate as the nearest year.
0
2
4
6
8
10
12
14
16
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
Annual prevalence (percentage)
Aged 12 years and older, United States
Aged 55–64 years, United States
Aged 15–64 years, European Union
Aged 55–64 years, European Union
0
2
4
6
8
10
12
14
16
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
Annual prevalence (percentage)
Aged 12 years and older, United States
Aged 55–64 years, United States
Aged 15–64 years, European Union
Aged 55–64 years, European Union
1.0
1.4
2.2
3.6
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
European
Union
United
States
European
Union
United
States
General population 55–64 years
Ratio of prevalence
(most recent year compared with 2006)
1.0
1.4
2.2
3.6
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
European
Union
United
States
European
Union
United
States
General population 55–64 years
Ratio of prevalence
(most recent year compared with 2006)
Ratio of 1 indicates
no change
52
WORLD DRUG REPORT 2018
attention has been paid to substance use disorders
among older people, with insufficient research into
and evidence on interventions for their treatment,
and with limited discussion on appropriate treat-
ment services.
298, 299, 300, 301
In combination with medical and psychiatric prob-
lems, older drug users commonly live with the
negative social consequences of long-term drug use.
These are important considerations in the provision
of effective treatment. Older drug users are more
likely to be socially and economically disadvantaged
and marginalized, with a greater chance of having
experienced homelessness or periods of incarcera-
tion. Social exclusion and isolation from family and
friends and a lack of social support are experienced
more often and more acutely by older drug users
than their peers or younger drug users. The absence
of social support is an important predictor of
relapse.
302, 303, 304
Drug-related treatment increases among
older people who use drugs in the United
States
Some of the most comprehensive and detailed treat-
ment data available come from the United States.
According to the latest data available from that
Royal College of Psychiatrists, (London, Royal College of
Psychiatrists, 2011).
297 Nick Doukas, “Older adults in methadone maintenance
treatment: a literature review”, Journal of Social Work
Practice in the Addictions, vol. 11, No. 3 (2011), pp. 230–
244.
298 Anne Marie Carew and Catherine Comiskey, “Treatment
for opioid use and outcomes in older adults: a systematic
literature review”, Drug and Alcohol Dependence, vol.182,
(2018), pp. 48–57.
299 Alexis Kuerbis and Paul Sacco, “A review of existing
treatments for substance abuse among the elderly and
recommendations for future directions, Substance Abuse:
Research and Treatment, vol. 7 (2013), pp. 13–37.
300 Wu and Blazer, “Illicit and nonmedical drug use among
older adults: a review”.
301 Orion Mowbray and Adam Quinn, “A scoping review of
treatments for older adults with substance use problems”,
Research on Social Work Practice, vol. 26, No. 1 (2016),pp.
74–87.
302 Michelle R. Lofwall and others, “Characteristics of older
opioid maintenance patients”, Journal of Substance Abuse
Treatment, vol. 28, No. 3 (2005), pp. 265–272.
303 Selected Issue 2010.
304 Yih-Ing Hser, “Predicting long-term stable recovery from
heroin addiction: findings from a 33-year follow-up study”,
Journal of Addictive Diseases, vol. 26, No. 1 (2007), pp.
51–60.
Drug treatment among older people
who use drugs
Ageing drug users face multiple health
issues
The physical ageing process can be accelerated by
the cumulative effects of drug use, including experi-
ence of prior drug overdoses and increased risk of
acquiring infectious diseases such as hepatitis C and
HIV through unsafe injecting practices. Older drug
users face health conditions that normally occur
with increasing frequency with older age, such as
degenerative disorders, circulatory and respiratory
problems and diabetes, but at higher rates than
among their non-drug using peers. Older drug users
also experience mental health issues at higher levels
than their peers or younger drug users.
290, 291, 292,
293, 294
Challenges for drug treatment and care
The development of drug use disorders and depend-
ence results from a complex interaction between
repeated exposure to drugs on the one hand, and
biological, psychosocial and social factors on the
other. Effective treatment for such a complex,
chronic condition as drug dependence requires con-
tinuing care and interaction across many disciplines,
such as pharmacological, behavioural therapy and
social support.
295
Numerous challenges exist in pro
-
viding treatment interventions and care for substance
use that are specific to, or more pronounced for,
older drug users.
Owing to the possible simultaneous presence of a
range of conditions, the complicated physical health
needs of older drug users make drug dependence
treatment more complex.
296, 297
Historically, little
290 EMCDDA, Health and Social Responses to Drug Problems:
a European Guide (Luxembourg, Publications Office of the
European Union, 2017).
291 Selected Issue 2010.
292 Caryl M. Beynon and others, “Self reported health status,
and health service contact, of illicit drug users aged 50 and
over: a qualitative interview study in Merseyside, United
Kingdom”, BMC Geriatrics, vol. 9, No. 45 (2009).
293 Lisa Johnston and others, “Responding to the needs of
ageing drug users” (EMCDDA, 2017).
294 Caryl M. Beynon, “Drug use and ageing”.
295 UNODC and WHO, “Principles of drug dependence
treatment” discussion paper, March 2008.
296 Ilana Crome and others, Our Invisible Addicts: First Report
of the Older Persons’ Substance Misuse Working Group of the
53
DRUGS AND AGE C. Drugs and older people
4
relatively low, in 2014 those aged 50 and older
accounted for more than one third of the total, up
from roughly 1 in 10 a decade earlier. The proportion
of treatment admissions for those aged 50 and older
who were referred through the court or criminal
justice system declined slightly over the period
1992–2012, from 29 per cent to 25 per cent.
307
Treatment for the use of opioids in
Europe – an ageing cohort of people
who use heroin
In Europe, opioid users, particularly those who
inject, currently represent a substantial proportion
of the drug treatment population and have tradi-
tionally represented the largest group requiring
specialized drug treatment. Although the number
of opioid users entering treatment is declining, the
proportion of clients aged over 40 entering treat-
ment for opioid use increased from 1 in 5 in 2006
to 1 in 3 in 2013. The evidence points to a large
307 United States, Department of Health and Human Services,
Substance Abuse and Mental Health Services Administra-
tion, Center for Behavioral Health Statistics and Quality,
Treatment Episode Data Set: Admissions (TEDS-A) Concat-
enated, 1992 to 2012, ICPSR 25221 (Ann Arbor, Michi-
gan, Inter-university Consortium for Political and Social
Research, 2015).
country, the number of admissions to drug use treat-
ment services for those aged 50 and older increased
by 59 per cent over the period 2004–2014. This age
group is increasingly prominent in treatment admis-
sions, with the proportion of those 50 and older in
all treatment admissions nearly doubling to 10.4
per cent during that period.
305, 306
The increasing number and prominence of those
aged 50 and older who were admitted to treatment
services during that period was observed for all drug
types. For cocaine in particular, the proportion of
all those admitted who were aged 50 and older
increased substantially. Although the number of
admissions to treatment for the use of sedatives was
305 United States, Department of Health and Human
Services, Substance Abuse and Mental Health Services
Administration, Office of Applied Studies, Treatment
Episode Data Set (TEDS): 1994–2004–National Admissions
to Substance Abuse Treatment Services, DASIS Series S-33,
DHHS Publication No. SMA 06-4180, (Rockville,
Maryland, 2006).
306 United States, Department of Health and Human
Services, Substance Abuse and Mental Health Services
Administration, Center for Behavioral Health Statistics and
Quality, Treatment Episode Data Set (TEDS): 2004–2014–
National Admissions to Substance Abuse Treatment Services,
BHSIS Series S-84, HHS Publication No. SMA 16-4986
(Rockville, Maryland, 2016).
Fig. 18
Trends in the number and proportion of those aged 50 and older in admissions to
treatment related to drug use, United States, 2004–2014
Source: United States, Department of Health and Human Services, Substance Abuse and Mental Health Services Administration,
Office of Applied Studies, Treatment Episode Data Set (TEDS): 1994–2004 – National Admissions to Substance Abuse Treatment
Services, DASIS Series: S-33, DHHS Publication No. (SMA) 06-4180 (Rockville, Maryland, 2006); and United States, Department of
Health and Human Services, Substance Abuse and Mental Health Services Administration, Center for Behavioral Health Statistics
and Quality, Treatment Episode Data Set (TEDS): 2004–2014 – National Admissions to Substance Abuse Treatment Services, BHSIS
Series S-84, HHS Publication No. (SMA) 16-4986 (Rockville, Maryland, 2016).
Note: In the left chart showing the number of admissions to treatment, “All admissions” are plotted on the left axis, while admissions by
specific drug types are plotted on the right axis.
-
10
20
30
40
50
60
0
20
40
60
80
100
120
All admissions
Heroin
Smoked cocaine
Other opiates
Stimulants
Cannabis
Cocaine (non-smoked)
Tranquillizers
Sedatives
Number of people (thousands)
2004
2014
All
admissions
Heroin
Smoked
cocaine
Other
opiates
Stimulants
Cannabis
Cocaine
(non-smoked)
Tranquillizers
Sedatives
All
admissions
Cannabis
Stimulants
Other
opiates
Heroin
Tranquillizers
Cocaine
(non-smoked)
Smoked
cocaine
Sedatives
0
5
10
15
20
25
30
35
40
All admissions
Cannabis
Stimulants
Other opiates
Heroin
Tranquillizers
Cocaine (non-smoked)
Smoked cocaine
Sedatives
Proportion of people (percentage)
2004
2014
54
WORLD DRUG REPORT 2018
quarter (23 per cent) among those aged 15–29 years
and a large proportion (38 per cent) occurring
among those in the 30–49 age group. However, a
considerable proportion of deaths worldwide from
drug use disorders (39 per cent) do occur among
drug users aged 50 and older.
It should be noted that for those aged 50 and older,
deaths resulting from drug use disorders represent
a smaller proportion of total deaths from all causes
of mortality; deaths resulting from drug use disorders
account for a higher proportion of mortality among
younger people. As people get older, there is a greater
number of age-related causes of mortality.
However, during the period 2000–2015, there was
a rapid increase globally in the number of deaths
resulting from drug use disorders among those aged
50 and older. This increase was more pronounced
than among drug users under the age of 50. For
those under the age of 50, deaths resulting from
ageing cohort of opioid users who started injecting
heroin during the heroin “epidemics” of the 1980s
and 1990s and who have shaped and characterized
current European specialist and low-threshold treat-
ment systems.
308
Current lack of response to a growing
problem
Particular and wide-ranging health issues arise from
drug use by older users, in particular for those with
a history of drug use disorders and dependence.
Treatment for substance use is more complicated
because of these concurrent mental and physical
health disorders. The lack of evidence on what treat-
ment works best for older drug users also exacerbates
the situation. This is a relatively recent phenomenon
and there is some concern that the infrastructure is
not in place to deal with the growing numbers of
older drug users and their health needs over the
coming decades.
In general, the development of specific interventions
or services for older drug users has yet to be consid-
ered a priority, possibly due to the lower prevalence
of drug use among older people than the younger
population. For example, there were no explicit ref-
erences to older users in the drug strategies of
European countries in 2010, and the situation has
changed little since. Specialized treatment and care
programmes for older drug users are rare in Europe,
with most initiatives directed towards younger peo-
ple.
309, 310
Drug-related deaths among older
people who use drugs
Dying as a result of the use of drugs is clearly the
most extreme outcome. Although those who die
from drug use disorders (deaths that are directly
caused by the use of drugs) are mostly younger
people, those aged 50 and older still constitute a
sizeable proportion. Among deaths from all causes
of mortality globally in 2015, the largest proportion
(53 per cent) occurred among those aged 70 and
above. Deaths resulting from drug use disorders
occur at a relatively young age, with almost one
308 Alessandro Pirona and others, “Ageing and addiction:
challenges for treatment systems” EMCDDA Poster Series
(Lisbon, September 2015).
309 Selected Issue 2010.
310 Johnston and others, “Responding to the needs of ageing
drug users”.
Fig. 19
Deaths resulting from drug use disor-
ders and from all causes of mortality,
by age group, worldwide, 2015
Source: WHO, Global Health Estimates 2015: Deaths by Cause,
Age, Sex, by Country and by Region, 2000–2015 (Geneva,
2016).
6%
12%
11%
18%
53%
All causes of mortality
23%
38%
15%
10%
14%
Drug use disorders
15–29 years
30–49 years
50–59 years
60–69 years
70 years and older
55
DRUGS AND AGE C. Drugs and older people
4
drug use disorders increased by one third, but for
those aged 50 and older, the number more than
doubled. Those 50 and older also accounted for an
increasing proportion of deaths resulting from drug
use disorders: while in 2000, 27 per cent of all deaths
from drug use disorders were among people aged
50 and older, by 2015 that proportion had risen to
39 per cent.
The increasing number of deaths resulting from
drug use disorders among those aged 50 and older,
and the increasing proportion of all such deaths
represented by that age group, is consistent across
all regions. In particular, in the Western Pacific
311
and in the Americas, deaths resulting from drug use
disorders among those aged 50 and older rose more
than threefold over the period 2000–2015.
In Europe, the number of overdose deaths increased
between 2006 and 2013 for those aged 40 and older,
but declined for those under 40, in part a manifes-
tation of the ageing population of opioid users.
312
In the United Kingdom, which accounts for almost
one third of overdose deaths reported in Europe,
313
there has been a sharp rise in the total number
of deaths involving heroin and/or morphine since
2012. An ageing cohort of heroin users, increased
purity and availability of the drug and changes in
the specific drugs taken alongside heroin and/or
morphine have contributed to this rise.
314
Globally, three quarters of deaths resulting from
drug use disorders among those 50 and older are
associated with the use of opioids. Deaths associated
311 In the WHO classification, the Western Pacific region
includes Cambodia, China, Japan, Malaysia, Mongolia, the
Philippines, the Republic of Korea and Viet Nam, as well as
Australia and New Zealand and the Pacific island countries.
312 Pirona and others, “Ageing and addiction”.
313 EMCDDA, European Drug Report 2017: Trends and
Developments (Luxembourg, Publications Office of the
European Union, 2017).
314 United Kingdom, Office for National Statistics, “Deaths
related to drug poisoning in England and Wales, 2015
registrations”, Statistical Bulletin (September 2016).
Fig. 20
Proportion of deaths resulting from drug use disorders among deaths from all causes,
by age group, worldwide, 2015
Source: WHO, Global Health Estimates 2015: Deaths by Cause, Age, Sex, by Country and by Region, 2000–2015 (Geneva, 2016).
Fig. 21
Deaths resulting from drug use
disorders, by age group, worldwide,
2000–2015
Source: WHO, Global Health Estimates 2015: Deaths by Cause,
Age, Sex, by Country and by Region, 2000–2015 (Geneva,
2016).
0
20,000
40,000
60,000
80,000
100,000
120,000
140,000
160,000
180,000
2000 2005 2010 2015
Number of deaths from
drug use disorders
Under 50 years 50–59 years
60–69 years 70 years and older
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Both sexes
Male
Female
Both sexes
Male
Female
Both sexes
Male
Female
Both sexes
Male
Female
Both sexes
Male
Female
Both sexes
Male
Female
All ages 15–29 years 30–49 years 50–59 years 60–69 years 70 years and
older
Percentage
56
WORLD DRUG REPORT 2018
Fig. 22
Deaths resulting from drug use disorders, by age group and region, 2000–2015
Source: WHO, Global Health Estimates 2015: Deaths by Cause, Age, Sex, by Country and by Region, 2000–2015 (Geneva, 2016).
Note: Regions correspond to the classifications used by WHO.
with cocaine use disorders and amphetamine use
disorders each account for about 6 per cent, and
those associated with the use of other drugs make
up the remaining 13 per cent.
315
This distribution
is a reflection of a number of factors: the ability to
identify different substances as the underlying cause
of death, different historical patterns of drug use
and the size of the populations using different drugs,
and the availability and effectiveness of treatment
options that may extend the life of drug users.
315 WHO, Global Health Estimates 2015: Deaths by Cause,
Age, Sex, by Country and by Region, 2000–2015 (Geneva,
2016).
Fig. 23
Deaths resulting from drug use
disorders, by main drug categories
and age, worldwide, 2015
Source: WHO, Global Health Estimates 2015: Deaths by Cause,
Age, Sex, by Country and by Region, 2000–2015 (Geneva,
2016).
0
10,000
20,000
30,000
40,000
50,000
60,000
Opioid
use disorders
Cocaine
use disorders
Amphetami ne
use disorders
Cannabis
use disorders
Other drug
use disorders
Number of deaths
15–29 years 30–49 years
50 years and older
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
45,000
50,000
2000
2005
2010
2015
2000
2005
2010
2015
2000
2005
2010
2015
2000
2005
2010
2015
2000
2005
2010
2015
2000
2005
2010
2015
Americas Europe Eastern
Mediterranean
Africa South-East
Asia
Western
Pacific
Number of deaths
15–29 years 30–49 years 50–59 years 60–69 years
70 years and older
57
GLOSSARY
amphetamine-type stimulants — a group of substances
composed of synthetic stimulants controlled under the
Convention on Psychotropic Substances of 1971 and
from the group of substances called amphetamines,
which includes amphetamine, methamphetamine,
methcathinone and the “ecstasy”-group substances
(3,4-methylenedioxymethamphetamine (MDMA) and
its analogues).
amphetamines — a group of amphetamine-type
stimulants that includes amphetamine and
methamphetamine.
annual prevalence — the total number of people of a
given age range who have used a given drug at least
once in the past year, divided by the number of people
of the given age range, and expressed as a percentage.
coca paste (or coca base) — an extract of the leaves of
the coca bush. Purification of coca paste yields cocaine
(base and hydrochloride).
“crack” cocaine — cocaine base obtained from cocaine
hydrochloride through conversion processes to make
it suitable for smoking.
cocaine salt — cocaine hydrochloride.
drug use — use of controlled psychoactive substances
for non-medical and non-scientific purposes, unless
otherwise specified.
new psychoactive substances — substances of abuse,
either in a pure form or a preparation, that are not
controlled under the Single Convention on Narcotic
Drugs of 1961 or the 1971 Convention, but that may
pose a public health threat. In this context, the term
“new” does not necessarily refer to new inventions but
to substances that have recently become available.
opiates — a subset of opioids comprising the various
products derived from the opium poppy plant, includ-
ing opium, morphine and heroin.
opioids — a generic term applied to alkaloids from
opium poppy (opiates), their synthetic analogues
(mainly prescription or pharmaceutical opioids) and
compounds synthesized in the body.
problem drug users — people who engage in the high-
risk consumption of drugs; for example, people who
inject drugs, people who use drugs on a daily basis
and/or people diagnosed with drug use disorders
(harmful use or drug dependence), based on clinical
criteria as contained in the Diagnostic and Statistical
Manual of Mental Disorders (fifth edition) of the
American Psychiatric Association, or the International
Classification of Diseases and Related Health Problems
(tenth revision) of the World Health Organization.
people who suffer from drug use disorders/people with
drug use disorders — a subset of people who use drugs.
People with drug use disorders need treatment, health
and social care and rehabilitation. Harmful use of sub-
stances and dependence are features of drug use
disorders.
harmful use of substances — defined in the International
Statistical Classification of Diseases and Related Health
Problems (tenth revision) as a pattern of use that causes
damage to physical or mental health.
dependence — defined in the International Statistical
Classification of Diseases and Related Health Problems
(tenth revision) as a cluster of physiological, behav-
ioural and cognitive phenomena in which the use of
a substance or a class of substances takes on a much
higher priority for a given individual than other behav-
iours that once had greater value. A central descriptive
characteristic of dependence syndrome is the desire
(often strong, sometimes overpowering) to take psy-
choactive drugs.
substance or drug use disorders — the Diagnostic and
Statistical Manual of Mental Disorders (fifth edition)
of the American Psychiatric Association also refers to
“drug or substance use disorder” as patterns of symp-
toms resulting from the use of a substance despite
experiencing problems as a result of using substances.
Depending on the number of symptoms identified,
substance use disorder may vary from moderate to
severe.
prevention of drug use and treatment of drug use disorders
— the aim of “prevention of drug use” is to prevent
or delay the initiation of drug use, as well as the tran-
sition to drug use disorders. Once a person develops
a drug use disorder, treatment, care and rehabilitation
are needed.
59
REGIONAL GROUPINGS
• East and South-East Asia: Brunei Darussalam,
Cambodia, China, Democratic People’s Republic
of Korea, Indonesia, Japan, Lao People’s
Democratic Republic, Malaysia, Mongolia,
Myanmar, Philippines, Republic of Korea,
Singapore, Thailand, Timor-Leste and Viet Nam
• South-West Asia: Afghanistan, Iran (Islamic
Republic of) and Pakistan
• Near and Middle East: Bahrain, Iraq, Israel,
Jordan, Kuwait, Lebanon, Oman, Qatar, Saudi
Arabia, State of Palestine, Syrian Arab Republic,
United Arab Emirates and Yemen
• South Asia: Bangladesh, Bhutan, India, Maldives,
Nepal and Sri Lanka
• Eastern Europe: Belarus, Republic of Moldova,
Russian Federation and Ukraine
• South-Eastern Europe: Albania, Bosnia and
Herzegovina, Bulgaria, Croatia, Montenegro,
Romania, Serbia, the former Yugoslav Republic of
Macedonia and Turkey
• Western and Central Europe: Andorra, Austria,
Belgium, Cyprus, Czechia, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary,
Iceland, Ireland, Italy, Latvia, Liechtenstein,
Lithuania, Luxembourg, Malta, Monaco,
Netherlands, Norway, Poland, Portugal, San
Marino, Slovakia, Slovenia, Spain, Sweden,
Switzerland and United Kingdom of Great Britain
and Northern Ireland
• Oceania: Australia, Fiji, Kiribati, Marshall Islands,
Micronesia (Federated States of), Nauru, New
Zealand, Palau, Papua New Guinea, Samoa,
Solomon Islands, Tonga, Tuvalu, Vanuatu and
small island territories
The World Drug Report uses a number of regional
and subregional designations. These are not official
designations, and are defined as follows:
• East Africa: Burundi, Comoros, Djibouti, Eritrea,
Ethiopia, Kenya, Madagascar, Mauritius, Rwanda,
Seychelles, Somalia, Uganda and United Republic
of Tanzania
• North Africa: Algeria, Egypt, Libya, Morocco,
South Sudan, Sudan and Tunisia
• Southern Africa: Angola, Botswana, Lesotho,
Malawi, Mozambique, Namibia, South Africa,
Swaziland, Zambia and Zimbabwe
• West and Central Africa: Benin, Burkina Faso,
Cabo Verde, Cameroon, Central African
Republic, Chad, Congo, Côte d’Ivoire,
Democratic Republic of the Congo, Equatorial
Guinea, Gabon, Gambia, Ghana, Guinea,
Guinea-Bissau, Liberia, Mali, Mauritania, Niger,
Nigeria, Sao Tome and Principe, Senegal, Sierra
Leone and Togo
• Caribbean: Antigua and Barbuda, Bahamas,
Barbados, Bermuda, Cuba, Dominica, Dominican
Republic, Grenada, Haiti, Jamaica, Saint Kitts
and Nevis, Saint Lucia, Saint Vincent and the
Grenadines and Trinidad and Tobago
• Central America: Belize, Costa Rica,
El Salvador, Guatemala, Honduras, Nicaragua and
Panama
• North America: Canada, Mexico and United
States of America
• South America: Argentina, Bolivia (Plurinational
State of), Brazil, Chile, Colombia, Ecuador,
Guyana, Paraguay, Peru, Suriname, Uruguay and
Venezuela (Bolivarian Republic of)
• Central Asia and Transcaucasia: Armenia,
Azerbaijan, Georgia, Kazakhstan, Kyrgyzstan,
Tajikistan, Turkmenistan and Uzbekistan
9 789211 483048
ISBN 978-92-1-148304-8
Following last year’s 20
th
anniversary edition, the World Drug Report
2018 is again presented in a special five-booklet format designed
to enhance reader friendliness while maintaining the wealth of
information contained within.
Booklet 1 summarizes the content of the four subsequent substantive
booklets and presents policy implications drawn from their findings.
Booklet 2 provides a global overview of the latest estimates of and
trends in the supply, use and health consequences of drugs. Booklet 3
examines current estimates of and trends in the cultivation, production
and consumption of the three plant-based drugs (cocaine, opiates and
cannabis), reviews the latest developments in cannabis policies and
provides an analysis of the global synthetic drugs market, including
new psychoactive substances. Booklet 4 looks at the extent of drug
use across age groups, particularly among young and older people,
by reviewing the risks and vulnerabilities to drug use in young people,
the health and social consequences they experience and their role in
drug supply, as well as highlighting issues related to the health care
needs of older people who use drugs. Finally, Booklet 5 focuses on
the specific issues related to drug use among women, including the
social and health consequences of drug use and access to treatment
by women with drug use disorders; it also discusses the role played
by women in the drug supply chain.
Like all previous editions, the World Drug Report 2018 is aimed
at improving the understanding of the world drug problem and
contributing towards fostering greater international cooperation for
countering its impact on health and security.
The statistical annex is published on the UNODC website:
https://www.unodc.org/wdr2018
