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Factors Inuencing Vulnerability Towards Heroin
Addiction in a Pakistani Cohort
Shagufta Jabeen1, Muhammad Saqlain Raja1, Sadia Saeed1, Muhammad Mobeen Zafar1,
Rizwana Abdul Ghani1, Abid Mahmood1, Muhammad Fiaz2, Pakeeza Arzoo Shiaq1,
Shahid Mahmood Baig3, S.M. Saqlan Naqvi1 and Ghazala Kaukab Raja1*
1Department of Biochemistry, PMAS Arid Agriculture University, Rawalpindi, Pakistan
2Department of Medicine, Shaheed Zulqar Ali Bhutto Medical University, Islamabad, Pakistan
3National Institute for Biotechnology and Genetic Engineering, Faisalabad, Pakistan
Article Information
Received 10 August 2016
Revised 31 August 2016
Accepted 17 September 2016
Available online 02 November 2016
Authors’ Contributions
GKR, SMSN and SMB were involved
in study design, data analyses and
interpretation. SJ collected data and
drafted the manuscript. MS analyzed the
data. SS helped in manuscript writing.
All other authors participated in data
analysis and interpretation.
Key words
Drug, Stress, Peer pressure, Multifactorial
Addiction to opioids including other illicit drugs is a chronic, relapsing multifactorial disorder of brain and, if left untreated, major
medical, social, and economic problems arise. Drug addiction is among major health issues faced by the World including Pakistan
with an alarming annual increase in heroin addicts. The study was designed to identify the socio-demographic risk factors
contributing to increasing susceptibility to heroin addiction in Pakistani populations. In this epidemiological study subjects were
interviewed through a comprehensive questionnaire consisting of open and closed-ended questions. Data regarding key factors
such as age and ethnicity, communal domain, education level, employment status and demographic factors (drug route, drug dose)
have bearing upon heroin addiction was collected. Descriptive and inferential statistics were used for data analysis. Early age
of addiction onset, low literacy rate, peer pressure, occupation type, and stress are among risk factors increasing susceptibility
towards heroin addiction in our studied cohort. Drug abuse initiated at an early age seems to trigger transition to heroin addiction
under the inuence of environmental risk factors.
INTRODUCTION
Drugs categorized as stimulants, sedatives, hallucinogens
and opioids are being abused throughout the world
including Pakistan. According to Koob and LeMoal (1997)
dsyregulation of the brain reward mechanism is induced by
repeated drug abuse with subsequent allostasis, the ability to
achieve stability through change. Opioids, the highly addictive
narcotics are clinically important analgesics and used for pain
management whereas their abuse often results in development
of tolerance, dependence, and overdose (Fischer et al., 2006a,
2006b). Mu-opioids receptors in central nervous system are
the target sites to award the effects of opioids that particularly
refers to natural, semi-synthetic, and synthetic chemicals
(Fornasari, 2012). Opioids addiction, a complex relapsing
brain disorder is characterized by compulsory drug seeking,
drug abuse, tolerance and physical dependence in spite of
harmful consequences (Krantz and Mehler, 2004). Different
internal and external environmental factors including an
addict’s mindset, social inuences like home environment,
peer pressure and response to stress and stressors may also
contribute to opiate addiction vulnerability (Kreek et al., 2012).
Multiple external/environmental factors with varying degree
of contribution at individual level results in increased risk of
opioid dependence development (Weinberg, 2001). Regarding
risk factors an early antisocial behavior, anxiety, depression,
socioeconomic status, academic failure, hyperactivity physical/
sexual abuse and history of substance dependence in family
* Corresponding author: ghazala@uaar.edu.pk
0030-9923/2016/0004-1161 $ 8.00/0
Copyright 2016 Zoological Society of Pakistan
are considered as the major contributing risks (Kilpatrick et
al., 2000; Ronel and Levy-Cahana, 2011; Zapata et al., 1998).
Moreover 1st drug attempt at an early age, poor academic
performance and psychiatric history are likely to increase the
frequency of substance use (Tsuang et al., 1999). In the context
of Pakistan opioids are commonly abused but heroin is one of the
major drugs of addiction in young boys and men, poses massive
personal and public health costs. Inter-individual variability
regarding vulnerability to addiction has been reported. Being a
complex disease it can be inuenced by a multitude of highly
entangled factors; behavioral, environmental, developmental
including gender and ethnicity, and genetics. However the
vulnerability towards addiction increases with an increase
in the number of predisposing risk factors clustering in an
individual while protective factors reduce the risk of addiction
development (NIDA, 2014). Though the magnitude and
severity of problem varies, Pakistanis are extensively exposed
to illegal opium, heroin tracking and abuse (Malik and Sarfaraz,
2011). Based on the data presented in United Nations Ofce on
Drugs and Crime, there are 6.7 million (aged 15-64 years) total
drug abusers while 0.8 million regular heroin users in Pakistan
with an annual consumption of 44 tons of heroin (UNODC,
2013). A report by Anti-Narcotics Force of Pakistan (2006-2007) has
focused on dierent factors responsible for increasing prevalence of
drug abuse in Pakistan. Some of the key factors include ease of access
of drug at very low prices, illiteracy/low education level, peer pressure,
social and family stress, etc. (Aslam, 2015; Aslam et al., 2011).
Like many common disorders with multifactorial etiology,
external factors play an important role in development of heroin
addiction. Therefore, present study was designed to investigate
the factors associated with heroin addiction vulnerability in
Pakistani populations.
ABSTRACT
Pakistan J. Zool., vol. 49(1), pp 95-99, 2017. DOI: http://dx.doi.org/10.17582/journal.pjz/2017.49.1.95.99
96
MATERIALS AND METHODS
We conducted the study to explore the external
environmental/socioeconomic aspects of heroin addicts in
Pakistan. The study is approved by the Ethics Committee of
Pir Mehr Ali Shah Arid Agriculture University Rawalpindi,
Pakistan for the Use of Human Subjects. Data was collected
using a comprehensive questionnaire and a written
informed consent was obtained from all study subjects.
To investigate the environmental factors we included a
random sample of 540 male heroin addicts admitted in
different drug rehabilitation centers/hospitals. Among
socio-demographic/external characteristics of studied
population; age (onset of drug addiction), literacy level,
daily drug dose, ethnicity, communal domain and stress in
case group were computed. The subjects were divided into
three age groups; <20 years, 21-40 years and >40 years.
The daily drug dose was grouped into <250 mg, 250-
1000 mg and >1000 mg/day and ethnicity was recorded
under three major ethnic groups; Punjabis, Pakhtoons
and “Others” (include miscellaneous ethnic groups). The
external/environmental risk factors were also categorized
as communal domain, stress and “others”. Though all cases
included in study were heroin addicts, the frequencies of
different drugs being used in different age groups before
transition to heroin addiction was also investigated.
Table I.- Descriptive statistics of study population.
Frequency (%)
<20 21-40 >40
Onset age for Heroin use 39.61 57.49 2.90
Tobacco smoking 84.91 14.79 0.30
Marijuana use 80.50 19.20 0.31
Alcohol drinking 75.81 24.19 0.00
Daily drug dose <250 mg 12.4
250-1000 mg 23
>1000mg 64.5
Ethnicity Punjabi 64
Pakhtoon 27.05
Others 8.95
Risk factors
(External /
Environmental)
Communal domain 73.95
Stress 18.14
Others 7.91
Statistical analysis
Descriptive and inferential statistics were used to draw
the conclusions. Onset of addiction in different age groups,
daily drug dose, prevalence of addicts in different ethnic
groups and risk factors were estimated using frequency
estimation. Association of addiction with age, ethnicity, and
literacy level and employment type was computed using
multinomial logistic regression and odds ratio (OR) was
calculated. Signicance level for all analysis was ≤0.05.
SPSS v.21 software was used for analysis.
RESULTS
As presented in Table I, the frequency of addictive
drugs abuse is higher in <20 years age group as compared
to the 21-40 and also >40 years. Among total study subjects
64% were Punjabis, 27.05% Pakhtoons, and 8.95% were
from “Other” ethnic groups. The frequency of the onset
of drug abuse in <20 years group is as follows; tobacco
smoking (84.91%), marijuana use (80.50%), alcohol
drinking (75.81%) and heroin (39.61%). In case of 21-40
and >40 years age groups, the drug abuse frequency for all
other drugs was low as compared to <20 years age group
except for heroin. However among heroin addicts, the
highest frequency (57.49%) was found in 21-40 years old
subjects (Table I). As for literacy levels the details of study
population are as follows: Primary 33%, Middle 24.9%,
Secondary 19.6%, Higher Secondary 10.7%, Graduation
5.2%, and Postgraduate 4.2%, respectively (Table II).
Table II.- Distribution of study subjects based on
literacy level, drug route, and daily drug intake.
Variables Frequency (%)
Literacy level
Primary 33
Middle 24.9
Secondary 19.6
Higher Secondary 10.7
Graduation 5.2
Postgraduate 4.2
Drug route
Smoking 60
Snifng 14
Injections 23
Snifng plus injections 5
Daily drug intake (Number of times)
Once/day 10.7
Twice/day 22.8
Thrice/day 66.1
>Thrice/day 41.1
Data related to the route of drug administration
indicates smoking 60%, snifng 14%, injections 23%,
snifng plus injections 5% (Table II). As for the frequency
of daily drug use, 41.1% were using >3 times/day, 66.1%
were using thrice in a day, 22.8% were on a twice use/day
whereas 10.7% were on a single time use/day. As for the
contribution of external/environmental risk factors, stress
contributed 18.4% towards drug addiction and 7.9 % in case
S. Jabeen et al.
97
of category “others”. It is worth mentioning that category
“others” is a combination of multiple factors including; urge,
company, poverty, unawareness, anger, drug trafcking,
home environment, and curiosity for experiencing drugs
while stress is also a part of it (Table I). The analyses
of demographic variables with drug addiction showed
high prevalence of drug users among individuals having
occupations like eld workers (laborers), shopkeepers and
drivers. Analysis also indicated strong association among
addiction and occupations: eld workers/laborers (OR=
2.07 CI = 1.24-3.44, p=0.005), shopkeepers (OR= 1.93
CI=1.06-3.54, p=0.003) and drivers (OR= 1.44 CI=1.77-
2.66, p=0.04) (Table III).
Table III.- Association of study variables with heroin
addiction.
Study variables Heroin addiction p-value
OR (95% CI)
Age in years (21-40 years as reference group)
<20 1.23 (0.58-2.66) 0.58
>41 1.10 (0.6-1.8) 0.69
Ethnicity (Punjabi as reference group)
Pakhtoon 1.03 (0.53-1.99) 0.94
Other Ethnicity 1.26 (0.62-2.57) 0.52
Occupation (Ofce employee as reference group)
Field worker (laborer) 2.07 (1.24-3.44) 0.005
Shopkeeper 1.93 (1.06-3.54) 0.003
Driver 1.44 (1.77-2.66) 0.04
Signicance levels p-value ≤0.05.
DISCUSSION
Opioids addiction is interplay of extrinsic and intrinsic
factors an individual is exposed to and may contribute
towards addictive risk phenotypes/behaviors. In current
study the contribution of key socio/demographic factors
towards heroin addiction vulnerability was explored. This
study found supporting evidence for a critical role of traits
like age, communal domain, low literacy level, employment
status and stress as predisposing risk factors of heroin
addiction in Pakistani cohort. In addition invasive heroin
administration route contributed towards higher risk of
health threatening blood borne disease/infections. Besides
a trend towards overdose is another key factor related to
heroin addiction. Among demographic risk factors of
heroin addiction, individuals starting addictive drugs at
an early age especially adolescence is considered amongst
heightened risk for substance use disorder (Schepis et al.,
2008). Though ethnic background of an individual has not
been generally considered among demographic factors
predisposing to drug addiction, our results tend to indicate
higher proportion of Punjabi ethnicity in our study cohort.
Although study subjects were sampled randomly but a
higher frequency of Punjabi group may be due to the reason
that samples were collected from regions heavily populated
with Punjabis. As for age, overall our results emphasize
that younger subjects (<20 years) are highly prone to
drugs of abuse as compared to the older age groups. A high
prevalence of marijuana, alcohol and tobacco encountered
among adolescents clearly highlights this age group is
highly susceptible to early onset of substance abuse. Our
results also support previous ndings that individuals
starting drug use in young age are also at increased risk of
substance dependence (Adriani et al., 2003; Swartzwelder
et al., 1998). However, the onset of heroin abuse was higher
in adult population (21-40 years age) group as compared
to the <20 years. The age specic varying trends of heroin
addiction could be attributed to multiple factors including
the type of drugs (tobacco, marijuana, alcohol, opium)
an individual rst attempted before transition to opioids.
Another important factor is easy access to addictive drugs
other than heroin and their availability. Furthermore, the
high price of heroin might be resulting in its use at later ages
rather than adolescence and variation in daily drug dose. It
is evident from literature that heroin overdose is one of the
major reasons of deaths among addicts (Darke and Duou,
2016; Darke and Hall, 2003; Rudd et al., 2016). About 65%
of heroin addicts use average daily drug dose between 150-
250 mg (Rehab-International, 2016). A smaller fraction
of our addicted population (12.4%) was at <250 mg daily
drug dose, 23% were within the range of 250mg-1000mg
while majority of the subjects (64.5%) were at multiple
daily doses >1000mg. The continued use of high drug
doses several times a day leads to the development of drug
tolerance leading to drug overdose (Kosten and George,
2002). A large proportion of our study subjects addicted to
higher heroin doses is an alarming situation as they could
be at high risk of drug overdose. It is indicated by literature
that heroin users have a high risk of death, especially death
due to overdose (Buster et al., 2002). However our results
do emphasize that potential interventions are needed to
reduce the rate of heroin overdose and related morbidity.
Moreover, the route of drug administration has been
reported to play role in drug over-dose like drugs taken via
injections pose higher risk which reduces substationally
when smoked (Darke et al., 2000). Though, it is important
to emphasize that death can, and does, result from smoking,
snorting, and swallowing heroin (Gossop et al., 1996;
Neaigus et al., 2001; Swift et al., 1999). In our study cohort
different gures regarding routes of heroin administration
exist; Smoking 60.2%, Injection 22.6%, Snifng 13.6%,
while 4.8% were using the combined routs of injection and
snifng. According to a report on Drug Use in Pakistan
(2013) 0.4% of heroin addicts in Pakistan use injections for
drug administration (UNODC, 2013). Data from current
study cohort reports 22.6% of the total study subjects
administrating heroin through injections. Moreover, addicts
tend to share needles while injecting drugs. These health
threatening practices are becoming a leading cause of
communicable diseases/infections especially HIV-AIDS,
Hepatitis, and Tuberculosis are highly prevalent among
drug users. Though majority of the subjects were un-aware
Heroin Addiction in Pakistan 97
98
of the diseases they were being exposed to infectious diseases
HIV, Hepatitis, Tuberculosis. In addition subjects in our
study cohort are also reported to acquire asthma, kidney and
skin related problems during heroin addiction development.
Among infectious diseases, Hepatitis C was highly prevalent
(16%) among our local addicts especially those using
needles with the company/fellows through whom they were
introduced to drug use. Besides a number of social factors
may also contribute either directly or indirectly contribute
towards the vulnerability of an individual towards drug
addiction.
Among social factors, peer pressure, illiteracy/low
education, employment status/occupation and related stresses
are been generally found to inuence substance abuse. It
is worth to mention that our data supports social inuence
(communal domain) being the leading cause of heroin
abuse in our population. A local study has also emphasized
peer pressure being the major factor of drugs abuse among
youth (Aslam et al., 2011; Mubeen and Sharif, 2007). These
ndings also highlight strong inuence of company at work
place or educational institution an individual is exposed to
and drug use.
With regards to the role of employment status/
occupation, we found signicant association of occupation
type with drug addiction in our study population. Our
results are in accordance with a previous report focused
on drug addict youth in Pakistan whom were not attending
any school/educational institutes (Mehdi et al., 2014).
It was mentioned that social factors especially working
environment rich in drug users are contributing signicantly
towards an increase in the number of drug addicts among
non-student youth of Pakistan. Among occupations, driving,
hawkers, factory employees and carpenters are highly prone
to cigarette smoking/drug use. It is worth to mention that
the peer pressure, already exposed to addiction, might
have more inuence on individuals with immature mental
approach and varying psychological pressures. Another
general trend commonly observed among addicts in Pakistan
is an initial start from tobacco smoking with a gradual
switch towards opium, cocaine, heroin including other
addicted substances (Nizami et al., 2011; Smart et al., 1982).
However stress has been shown to overpower all other social
factors. According to data collected from respondents, our
analysis revealed that stress is a major external risk factor
for an individual indulging in drug abuse in our population.
The population and epidemiological studies have conrmed
stress as an eminent marker increasing vulnerability towards
drug addiction and a major cause for higher relapse rate in
individuals previously treated for drug abuse (Sinha, 2008).
CONCLUSIONS
This is the rst study from Pakistan exploring
association of social and demographic factors increasing
vulnerability towards heroin addiction. It provides the
evidence that age, communal domain, employment type,
low literacy level, stress are signicant external contributing
risk factors for heroin addiction in our study cohort.
However drug administration routes and trend towards
higher drug dose contributed towards increased health risks
among addicts. Being complex and multifactorial disorder,
heroin addicts require multi-level intervention strategies to
address the biological, social and psychological elements of
the disorder. In order to effectively prevent and treat heroin
addiction cases understanding of the basic mechanisms
including comprehensive study of sociodemographic factors
contributing for its vulnerability is further required in
Pakistani population. Although our ndings are somewhat
similar to those previously reported in other populations,
we attempted to evaluate the factors that may help to design
better strategies for the prevention, control, and treatment
of illicit heroin use in Pakistani populations. In addition the
high risk addiction associated sociodemographic factors
identied in presented study could be highlighted to create
awareness at individual, family, peer, and government levels.
ACKNOWLEDGEMENTS
We are thankful to Higher Education Commission
Pakistan for funds for this study under 5000 Indigenous
Scholarship Scheme. We are also thankful to all the drug
rehabilitation centers and hospitals enrolled and assessed
subjects for this study.
Conict of interest statement
We declare that we have no conict of interest.
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