Journal of Mental Health and Human Behaviour

: 2014  |  Volume : 19  |  Issue : 2  |  Page : 62--68

Psychosocial factors associated with HIV-related high-risk injection behavior among people who inject drugs

Swati K Gupta, Atul Ambekar, Anju Dhawan, Manju Mehta 
 National Drug Dependence Treatment Centre and Department of Psychiatry, All India Institute of Medical Sciences, New Delhi, India

Correspondence Address:
Swati K Gupta
Department of Psychiatry, National Drug Dependence Treatment Centre, All India Institute of Medical Sciences, New Delhi - 110 029


Understanding factors affecting the risky injection practices among people who inject drugs (PWIDs) are critical toward identifying the transition from initial injecting to HIV seropositivity. Increasingly HIV prevention programs have been focusing on targeted interventions in such high-risk groups, which include addressing some of these factors. We reviewed the literature on factors associated with HIV-related high-risk injection behavior among PWIDs using electronic databases such as Pubmed and Google scholar. This was supplemented by manual search for non-indexed and grey literature. The factors studied include age and age of initiation, duration of use, concurrent alcohol use, social networks, stigma, and impact of the intervention. In general, there is a lack of studies from developing countries, and most of the literature are from western settings. Across studies, the risky injection practices have been consistently associated with early age of initiation and social network characteristics such as family member using injections, using injections with the sexual partner. However, studies have shown inconsistent association with current age, duration, and exposure to interventions for substance use disorders. Despite strong theoretical underpinning of a positive association, there is inadequate literature on factors such as alcohol abuse and stigma. This narrative review highlights the need for high-quality studies addressing factors associated with HIV-related high-risk injection behavior.

How to cite this article:
Gupta SK, Ambekar A, Dhawan A, Mehta M. Psychosocial factors associated with HIV-related high-risk injection behavior among people who inject drugs.J Mental Health Hum Behav 2014;19:62-68

How to cite this URL:
Gupta SK, Ambekar A, Dhawan A, Mehta M. Psychosocial factors associated with HIV-related high-risk injection behavior among people who inject drugs. J Mental Health Hum Behav [serial online] 2014 [cited 2020 Sep 30 ];19:62-68
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Full Text


People Who Inject Drugs (PWIDs) constitute a highly vulnerable group that carries dual risk of transmission of HIV/AIDS through risky sexual behavior as well as sharing of needles/syringes. In 2014, the United Nations Office on Drugs and Crime (UNODC) estimated that the average global prevalence of PWIDs is about 0.27% (range: 0.19-0.48) with huge regional variations. [1] In the Indian context, we have come a long way from the erroneous belief that PWIDs were a matter of concern only in the north-eastern states to an acceptance that injecting drug use is a pan-Indian phenomenon. [2],[3],[4],[5] Currently, the only nationwide estimates of prevalence of PWIDs in India come from a 2004 study, which showed prevalence of "ever" injecting ranges from 0.1% (in household) to 14% (in treatment seekers) among adult males. [6]

According to UNODC estimates, 13.1% of PWIDs have HIV globally. [1] In India, the proportion of PWIDs living with HIV ranges from 9.10 to 15.1%. [7] Unsafe injection practices among PWIDs are a common phenomenon. [2],[8] According to the 2004 survey, needle/syringe sharing ranged from 39% (Jamshedpur) to 86% (Imphal). Among treatment seekers, 7.7% reported "ever" sharing needles/syringes. Indirect sharing (e.g. sharing of the cotton swab, filter, and spoons, etc.) was also common. [6]

Unsafe injection practices include sharing of needles, syringes, and other paraphernalia. The term "sharing" tends to have two different connotations: First is called either "donor sharing" or "lending" or "distributive sharing," and the second is known as either "recipient sharing" or "borrowing" or "receptive sharing." [9] However, in common usage, most PWID do not distinguish between lending or borrowing and understand the term "sharing" to mean both. The preparation of injection also involves other equipment, like use of spoon, "cooker," water container, cotton, all of which may come in direct contact with blood and other infective agents, and thus, sharing of this equipment also poses a risk for spreading HIV infections. Box 1 highlights some of the commonly used terms with respect to high-risk injection behavior.


Over the years, various studies have looked into factors associated with HIV-related risky injection practices. The aim of this non-systematic review was to study the scientific literature for factors associated with sharing injection equipment among PWIDs.


This review drew on the published literature and included both peer-reviewed and non-peer-reviewed sources using electronic database searches and snowballing. Studies were identified using key-word search of electronic sources (PubMed and Google scholar). Search terms included combinations of "HIV," "high-risk behaviors," "context," "high-risk injection behavior," "psychological factors," "social network," and "sharing." Key peer-reviewed journals published in the English language were manually searched. Reference lists of articles were reviewed to identify other relevant studies. Though the focus of the current review was to present the recent studies, those published prior to the year 2000 were considered if they were found to be relevant or highly cited. Specific attempt was made to review studies published in developing countries. Wherever available, full texts of the identified studies were read, and key findings noted. Studies focusing purely on biological, economic and structural correlates of sharing were excluded.

 Results: Correlates of Sharing

Age and age of initiation

As early as 1980s, it was recognized that HIV-related risk behaviors varied by age. Early in the epidemic, a classical cross-sectional study noted higher HIV rates as well as risk behaviors in older as compared to younger PWIDs. [10] Since then, many studies have focused on age (older versus younger PWIDs) as well as age of initiation as correlates of HIV-related high-risk behaviors.

Studies focusing on age of initiation have consistently found a positive association between early age of initiation of substance use, propensity to engage in injecting drug use and subsequently risky injection practices. [11],[12] However, results with respect to age have been contradictory. Earlier studies using sample from both community as well as treatment-seeker revealed that age was negatively correlated with risky injection practices. [13],[14] However, recent, data from NIDA Cooperative Agreement for AIDS Community-Based Outreach/Intervention Research Program [11] and 2005-2008 National Survey of Drug Use and Health [15] indicated that older age was positively associated with high-risk injection behaviors.

There is strong evidence to suggest that earlier age of initiation is not only associated with a higher propensity to initiate injection use, but also indulge in various HIV-related high-risk behaviors including sharing practices. It can be hypothesized that beginning substance use early in life could be related to certain personality characteristics, which also predisposed the individual to later risk behaviors. Moreover, initiation into substances at an early age does not allow for normal development of personality and cognition and hence setting grounds for experimentation and risky activities.

The evidence is, however, contradictory with regard to age and risky injection practices; with the earlier studies indicating age to be negatively associated with risky injection practices, while the current studies (in the last 10 years) reporting older age to be positively correlated with high-risk injection behavior. Reasons for the inconsistent findings could be due to the difference in use of the terms "younger" and "older" and use of age as a proxy for duration in different studies. [16]

Duration of use

It has been hypothesized that like any other substance use, injecting drug use observes a progressive course. As the habit gets addictive, the user may become less cautious and share equipment and needles. Several large-scale studies and community-based surveys on PWIDs have reported that the high-risk behavior is directly correlated with duration of injection use and are lower in newer initiates. [17],[18],[19] Various risk-behaviors found in long-term PWIDs (LTPWIDs) have been-sharing needles, use of shooting galleries and "back-loading". [20] A study that included 912 PWIDs found that the duration of injection use ≥11 years was significantly associated with HIV infection and the significant correlates of sharing were-injecting at dealer's place and a history of tattooing. [21]

In contrast, other studies have reported that the risk of indulging in high-risk injection behavior tends to be the highest at the time of the first injection and tends to stabilize or decline thereafter. [22],[23],[24] In late 90's, Des Jarlais et al. [25] suggested that those who have initiated injections recently are a significant group because of their high potential to perpetuate, expand the existing HIV/AIDS epidemic among other injectors and probably extend it to new cohorts of non-injectors. Secondary analysis of data gathered from a large multi-centric "collaborative injecting drug users Study (CPWIDS-II)" with a sample size of 1836 PWIDs revealed that newer initiates, as compared to those using for more than 4 years, displayed higher frequency of risky behaviors including injecting with others, injecting more often, sharing injection equipment, preparation equipment and "back-loading." [26] Similar results have been reported from a longitudinal cohort study of PWIDs (n = 1158) from India, which found that compared to those who had initiated drug use ≥2 years, recent initiates were younger, had lower prevalence of HIV/HCV, were more likely to inject buprenorphine and indulge in risky injection practices. [27] In another recent study from India, involving about 1000 PWIDs from different parts of the country, about 79% reported sharing injections ever. Interestingly, about 82-88% of those who ever shared, reported the first instance of sharing within 1 month of initiation of IDU. [28]

Association between duration of injection use and risky injection practices remains debatable. Several large-scale epidemiological studies have reported that risky injection practices were more prevalent in LTPWIDs and have hypothesized that as injection use becomes a habit, individuals tend to become less cautious. However, another set of studies including data from developing countries like India have reported that newer initiates indulged in more high-risk behaviors as compared to those using injections for more than a couple of years. The main reasons for contradictory findings in this regard are variability in the definition of the term "recent onset," and use of purposive sampling that limits the generalizability of the data.

Social correlates and network characteristics

Various epidemiological researches (both qualitative and quantitative) have shown that the context of substance use (especially social network) is associated profoundly with sharing. Social network are defined by the social links between individuals that specify one or more types of relationships. [29] These relationships signify pathways through which information, material as well as blood-borne infections can be transmitted. Social networks can be understood either from the perspective of the individual (ego-centric) or as a collection of connected individuals (socio-centric). The behaviors of the members of a particular social network are mediated through social influence, social comparison process, and social norms. [30],[31] Peer behaviors are also found to exert an important influence on risky injection behaviors, which include prospective modes or verbalization of norms (explicit persuasion by peers) and descriptive norms or social modeling (observing and imitating to conform to peer behavior) wherein the latter exerts stronger influence on needle sharing. [32] Certain behavioral characteristics of the network and group members that have been studied are involvement in homosexual practices, modeling of sharing behavior, daily use of injectable heroin and secondary drug trade involvement. [33],[34],[35]

The social network characteristics are usually addressed in terms of their structure, composition and behavioral aspects. An understanding of these correlates could aid in developing and implementing network-oriented implementations. Structural aspects can be understood in terms of large network sizes, which translates to both stronger peer pressure as well as higher number of potential sources of contaminated equipment; [36] greater centrality or core positions associated with brokerage of equipment and drug exchange [37] and greater change in the network membership or high turnover, which makes sharing behavior more acceptable. [38]

Other studies on social network have focused on gender composition and have reported that males generally share with other men with whom they have a social bonding, who they injected or who injected them or with females with whom they have a sexual relationship; whereas women share with men with whom they share an intimate or sexual relationship and with whom they have discussed HIV risks. [39],[40],[41] Other social network areas that have been focused upon are higher risky injection practices in groups with younger PWIDs as they are more open to experimentation; [33],[39],[42] with individuals from lower socioeconomic status because of non-affordability of new syringes [34] and those with varying ethnicity. [43] Having family members who use drugs and involving more with PWIDs rather than with non-drug using people are also found to be significant social correlate of risky injection practices. [44],[45],[46]

In the Indian setting, there is a dearth of literature addressing the social network characteristics per se. However, one of the surveys carried out in Delhi and Imphal (n = 1600 PWIDs) highlighted the social and behavioral correlates of HIV-related high-risk behavior among PWIDs as illiteracy, lack of awareness of HIV and staying alone/unmarried. [47]

Social networks are associated profoundly with sharing injections and paraphernalia and are also one of the most widely studied areas. A literature search conducted from 1996 to 2007 found 104 articles on social correlates of IDU out of which 58 directly addressed social network as a correlate. [48] In the context of social network, it is necessary for studies to determine the group, which individuals observe as well as refer to. [49],[50] Some of the shortcomings of the studies focusing on social factors associated with sharing are lack of standard definition of "social network," less number of studies from non-North American sample, biases inherent in self-reporting, cross-sectional nature of the studies and use of egocentric perspective. [48] Despite these issues, social network seems to be playing a significant role in influencing the behaviors of its members through its structure, function, and norms and thus interventions should definitely focus on counteracting the negative influences of the group.

Concurrent use of alcohol

Consumption of alcohol is believed to be a determinant of both sexual, as well as drug-related high-risk behavior. [51],[52] One possible explanation can be that alcohol generally lowers behavioral inhibition and impairs judgment, which may propel an individual to act in a risky fashion. [53] As early as 1990s, various studies report a positive association between heavy drinking and high-risk sexual behaviors in PWIDs. However, the association between alcohol use and risky injection behavior was not studied much till the turn of the century. [54],[55]

Various studies using participants from needle-syringe exchange programs have reported that, as compared to those who did not use alcohol or used it very less, the odds of sharing needles/syringes was significantly higher in PWIDs with alcohol abuse. [56],[57],[58] Another study that recruited both male and female PWIDs from a detoxification program reported positive association between alcohol abuse and HIV-related high-risk behaviors; this risk was found to be higher in women as compared to men. [59]

A longitudinal study using data from the ALIVE cohort (n = 1,698 PWIDs) reported that risk behaviors (namely, non-injecting cocaine use, injecting drugs, men having sex with men and multiple sexual partners) were associated with higher alcohol consumption. [60] At follow-up, there was a decrease in overall alcohol use, binge-drinking, and also HIV-related high-risk behaviors.

However, the major limitations of all these studies have been their failure to look into event-level association between alcohol intoxication and risk behaviors, that is, whether alcohol use immediately preceded high-risk injection behavior. Till date, to the best of our knowledge, hardly any studies have looked into event-level association between alcohol use and high-risk injection practices. However, one of the recent studies has tried to address both global, as well as event-level association between alcohol intoxication and high-risk sexual behaviors. Analyzing data from 6,341 PWIDs entering detoxification or Methadone maintenance program between 1990 and 2004, a study has reported both global as well as event level association between alcohol intoxication and risky sexual behavior, especially if both partners were intoxicated. [61]

Although, concurrent use of alcohol has been consistently associated with high-risk sexual behaviors; its role in risky injection practices has not been studied adequately. Only a few studies have looked into this aspect. Though, these studies have found a positive association between alcohol abuse and high-risk injection practices, none of the studies have been able to either establish a causal relationship or event-level association, that is, use of alcohol immediately preceding injection sharing, which limits the reliability of the association between the two.


The traditional concepts of stigma have been concerned with those considered to have a "spoiled" identity and how those who are stigmatized internalize aspects of that identity. [62] The recent conceptualization of stigma highlights its dynamic process through a combination of labeling, stereotyping, discrimination, and loss of status. [63] In the context of substance use, it has been suggested that the attribution of and internalization of stigma can reduce the effectiveness of prevention as well as other harm-reduction activities. [64] As early as 1950s and 1960s, it was recognized that stigmatization also occurred within drug using groups, that is, "propensity by drug users [sic] to derogate other drug users [sic] in an attempt to raise their own status". [65] Various studies have reported that among HIV non-infected individuals, stigmatization was found to increase high-risk behaviors and among sexually active PLHWA (People Living with HIV/AIDS), experiences of HIV/AIDS discrimination led to an increased incidence of unsafe sexual behavior. [66],[67],[68]

A qualitative study involving pharmacies, PWIDs and other key persons involved with service delivery and planning, reported that "independent" pharmacies were more supportive and accepting of PWIDs as compared to those that were dependent on the government for their funding. The pharmacies tend to view the PWIDs as "undesirable, scary, and undeserving; likely to be "dodgy" and/or shoplifters." The PWIDs were able to pick the stigma from pharmacies, their staff, and other pharmacy consumers and avoided pharmacies in which they feared discrimination or felt too uncomfortable with. Within the PWID population, those who were homeless and shared injections were considered to be "irresponsible, dirty, lazy people… who had given up" by other PWIDs who were non-sharers and/or were staying at their homes. The authors further postulated that presence of stigma was also a major barrier in accessing harm-reduction service and thereby promoting high-risk behaviors. [69]

In a study from Chennai (India), 851 male PWIDs were recruited through street-outreach program. After adjusting for important variables (demographic, history of arrest or treatment in past year, age of starting injections, acquiescence bias), perceived stigma remained consistent and was significantly associated with frequency of injection use, sharing of needles and other equipment and having at least two high-risk injection behaviors per week in the past 6 months. [70]

People who inject drugs are a highly stigmatized group not only by the general population, but also by non-injecting substance users. Stigma is found to impact not only the various high-risk behavior but also treatment-seeking by PWIDs. Major studies have focused on stigma and its impact among HIV-positive individuals; however, less emphasis has been given on the direct impact of stigma on various high-risk behaviors. [71] Thus, it has been suggested that to develop prevention programs, more rigorous studies need to be undertaken to understand the relationship between stigma and HIV-related high-risk behaviors.

Impact of abstinence-oriented treatment

Many studies have tried to investigate whether treating substance use disorder has also been effective in reducing risky sexual behaviors of PWIDs, however, the results have been ambiguous and conflicting; with some studies showing reduction in some behaviors (for example, inconsistent condom use), while others showing no effect of treatment. One of the earliest reviews published in this regard was reported in 1990s by Des Jarlais, who reviewed studies till 1989 and concluded that "bringing IV drug users in treatment should be an effective method of protecting some of them from HIV infections." [72] Decreased HIV incidence have been reported in PWIDs attending needle-syringe exchange programs, [73] community outreach, [74] and substance-dependence treatment; indicating that PWIDs seem to be changing their behaviors due to interventions.

Longitudinal data from the Drug Abuse Treatment Outcome Studies found that both injection drug use and risky sexual behavior declined over time, with a maximum decline being reported in the 1 st year of follow-up. At 5-year follow-up, however, they found a sub-group of subjects (about 76%) with an increase in substance use. The authors found that this sub-group also had a high level of alcohol intake, psychiatric comorbidities, and arrests. [75]

A review of 19 published studies related to the effectiveness of various psychosocial interventions in changing high-risk behaviors. Of these, 15 studies directly examined behavioral outcomes. Effectiveness of the intervention in changing HIV-related high-risk behaviors was demonstrated in only eight studies and out of these only 50% were found to be methodologically sound. In nine studies, it was found that subjects reported lowered risk behaviors at follow-up regardless of whether they were placed in experimental or control conditions, which could be explained due to the "spill-over" effect from experimental to control condition, changes in social and secular trends, presence of subjects who were willing for behavioral changes, impact of HIV testing, and "Hawthorne effect." [76] Another review of 33 studies found that the treatment of substance use disorders decreased the risk of HIV infection by decreasing an overall frequency of injection use. However, the evidence was not strong (especially in the cross-sectional studies) toward changes in needle-sharing pattern or risky sexual behaviors. [77]

With respect to intervention, there are some indications that it may have some effect on HIV-related high-risk behaviors, especially injection related. However, literature seems to be sparse on sustainability of behavior changes over time. Furthermore, most studies have used self-report as a method of data collection and subjects have primarily been stable and highly motivated individuals (e.g. in methadone maintenance therapy) who may change irrespective of treatment provided.


People who inject drugs or PWIDs are a high-risk group with respect to HIV and other blood-borne infections. Alarmingly, the prevalence of HIV among PWIDs has been increasing in India. They carry a dual risk of transmission via sexual behavior as well as unsafe injection practices. Many PWIDs tend to engage in high-risk injecting behaviors, though factors influencing these behaviors have not been thoroughly studied The current review aimed to discuss recent literature on various factors associated with HIV-related risky injection behaviors, and have included individual factors like age and age of initiation; factors related to drugs-duration of use, concurrent use of alcohol; social factors such as stigma, social network, and impact of treatment. Across studies, the HIV-related high-risk injection behaviors have been consistently associated with early age of initiation as well as certain social network characteristics. However, findings have been inconsistent for factors such as age, duration, and impact of interventions Moreover, there is strong theoretical underpinning of a positive association between high-risk injection practices and alcohol use as well as presence of stigma, however, the literature is inadequate in this regard.

In general, some of the methodological limitations inherent in the studies reviewed have been lack of data from developing countries, use of non-random samples, literature comparing PWIDs taken from different setting, e.g. treatment-seekers versus non-treatment seekers; not focusing on gender-specific issues, use of self-report, which may be tinged with social bias, and use of different operational definition, for example, age is often substituted with duration of use in many studies.

At the research level, future studies should attempt to look into these shortcomings and address them in order to expand our understanding of these variables. It is also imperative at public health level, that programs that aim at prevention or curbing high-risk injection behavior in PWIDs must take these psychosocial correlates into account in order to plan and implement evidence-informed policies. Furthermore, these factors are also important to understand at a clinical level, so as to facilitate individually-tailored treatment plans to address these behaviors.


The primary aim of the current review was to understand the recent literature on various factors associated with HIV- related high-risk injection behaviors. During the process of the review, it came into focus that most of the literature in this regard is from developed countries and data from developing countries is sparse. It is, therefore, imperative to conduct research into these areas in developing nations in order to better understand this vulnerable population and plan scientifically, socially, economically, and culturally informed interventions.


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