Updating the infection risk reduction hierarchy: preventing transition into injection

Adapted "Break the Cycle for Avant Garde" intervention to reduce injection assisting and promoting behaviours in people who inject drugs in Tallinn, Estonia: A pre- post trial

In the context of established and emerging injection drug use epidemics, there is a need to prevent and avert injection drug use. We tested the hypothesis that an individual motivation and skills building counselling, adapted and enhanced from Hunt's Break the Cycle intervention targeting persons currently injecting drugs would lead to reduction in injection initiation-related behaviours among PWID in Tallinn, Estonia. For this quasi-experimental study, pre-post outcome measures included self-reported promoting behaviours (speaking positively about injecting to non-injectors, injecting in front of non-injectors, offering to give a first injection) and injection initiation behaviours (assisting with or giving a first injection) during the previous 6 months. Of 214 PWID recruited, 189 were retained (88.3%) for the follow-up at 6 months. The proportion of those who had injected in front of non-PWID significantly declined from 15.9% to 8.5%, and reporting assisting with 1st injection from 6.4% to 1.06%. Of the current injectors retained in the study, 17.5% reported not injecting drugs at the follow up. The intervention adapted for the use in the setting of high prevalence of HIV and relatively low prevalence of injection assisting, tested proved to be effective and safe.

Housing Instability, Structural Vulnerability, and Non-Fatal Opioid Overdoses Among People Who Use Heroin in Washington Heights, New York City

Nationally, opioid overdose remains strikingly persistent among people experiencing homelessness and housing instability. Limited information is available about the characteristics of this phenomenon in economically disadvantaged communities of color. This study sought to evaluate the association between key contextual factors and experiencing a non-fatal opioid overdose among people who use heroin in Washington Heights, New York City. We conducted a cross-sectional survey (N = 101) among participants seeking harm reduction services who reported heroin use in the last three months. Binary logistic regression models examined the association between key social and structural factors and the likelihood of ever experiencing a non-fatal opioid overdose and recently experiencing a non-fatal opioid overdose. The majority of the sample reported housing instability and lived in poverty; almost 42% were homeless. After adjustment, participants who injected heroin were more likely to have ever experienced a non-fatal opioid overdose. Also, younger participants who reported hunger in the last six months were more likely to have experienced a non-fatal opioid overdose in the last three months. Findings suggest the role of structural vulnerability in shaping overdose risk among the participants. Overdose prevention strategies should consider factors of the social and economic environment to mitigate barriers to accessing health and social services within the context of the current opioid crisis.

Involvement of people who inject drugs in injection initiation events: a cross-sectional analysis identifying similarities and differences across three North American settings

OBJECTIVES

People who inject drugs (PWID) play an integral role in facilitating the entry of others into injection drug use (IDU). We sought to assess factors influencing PWID in providing IDU initiation assistance across three distinct North American settings and to generate pooled measures of risk.

DESIGN

We employed data from three PWID cohort studies participating in PReventing Injecting by Modifying Existing Responses (PRIMER), for this cross-sectional analysis.

SETTING

Tijuana, Mexico; San Diego, USA; Vancouver, Canada.

PARTICIPANTS

A total of 2944 participants were included in this study (Tijuana: n=766, San Diego: n=353, Vancouver: n=1825).

MEASUREMENTS

The outcome was defined as recently (ie, past 6 months) assisting in an IDU initiation event. Independent variables of interest were identified from previous PRIMER analyses. Site-specific multiple modified Poisson regressions were fit. Pooled relative risks (pRR) were calculated and heterogeneity across sites was assessed via linear random effects models.

RESULTS

Evidence across all three sites indicated that having a history of providing IDU initiation assistance (pRR: 4.83, 95% CI: 3.49 to 6.66) and recently being stopped by law enforcement (pRR: 1.49, 95% CI: 1.07 to 2.07) were associated with a higher risk of providing assistance with IDU initiation; while recent opioid agonist treatment (OAT) enrolment (pRR: 0.64, 95% CI: 0.43 to 0.96) and no recent IDU (pRR: 0.21, 95% CI: 0.07 to 0.64) were associated with a lower risk. We identified substantial differences across site in the association of age (I²: 52%), recent housing insecurity (I²: 39%) and recent non-injection heroin use (I²: 78%).

CONCLUSION

We identified common and site-specific factors related to PWID's risk of assisting in IDU initiation events. Individuals reporting a history of assisting IDU initiations, being recently stopped by law enforcement, and recently injecting methamphetamine/speedball were more likely to have recently assisted an IDU initiation. Whereas those who reported not recently engaging in IDU and those recently enrolled in OAT were less likely to have done so. Interventions and harm reduction strategies aimed at reducing the harms of IDU should incorporate context-specific approaches to reduce the initiation of IDU.

Examining the gender composition of drug injecting initiation events: A mixed methods investigation of three North American contexts

BACKGROUND

Gender influences the health and social risks faced by individuals initiating drug injecting. Using mixed methods across three settings in North America, we investigated the gender composition of injection initiation events and the gendered risk environments in which they occurred.

METHODS

The PReventing Injecting by Modifying Existing Responses (PRIMER) study pooled data from three prospective community-recruited cohorts of people who inject drugs (PWID) in San Diego, USA, Vancouver, Canada, and Tijuana, Mexico. A qualitative subsample provided narrative data on their experiences of, and the contexts for, injection initiation events. Guided by Rhodes' risk environment framework, we examined the gender composition of initiation events stratified by city, and analyzed qualitative data using abductive thematic analyses.

RESULTS

Among 2,622 PWID (Tijuana: n = 531; San Diego: n = 352; Vancouver: n = 1,739), 112 (4.3%) reported providing initiation assistance to injection-naïve individuals in the previous six months. The proportion of gender concordant (e.g., male-male) initiation pairs varied, (χ2 = 10.32, p <0.001) with greater than expected concordance among pairs in Tijuana compared with those in Vancouver or San Diego. Sixty-one interviews provided context for the discrepancy across sites by highlighting the gendered injection initiation risk environments of prison/jail detention in Tijuana, intimate partnerships in San Diego, and overdose risk in Vancouver.

CONCLUSIONS

These results highlight how gender influences injection initiation events within spatial, social, and economic risk environments, and how this influence varies across settings. These findings can inform interventions to reduce the risk of injection initiation and related harms.

Prevalence and Correlates of Providing and Receiving Assistance With the Transition to Injection Drug Use

Preventing the transition to injection drug use is an important public health goal, as people who inject drugs (PWID) are at high risk for overdose and acquisition of infectious disease. Initiation into drug injection is primarily a social process, often involving PWID assistance. A better understanding of the epidemiology of this phenomenon would inform interventions to prevent injection initiation and to enhance safety when assistance is provided. We conducted a systematic review of the literature to 1) characterize the prevalence of receiving (among injection-naive persons) and providing (among PWID) help or guidance with the first drug injection and 2) identify correlates associated with these behaviors. Correlates were organized as substance use behaviors, health outcomes (e.g., human immunodeficiency virus infection), or factors describing an individual's social, economic, policy, or physical environment, defined by means of Rhodes' risk environments framework. After screening of 1,164 abstracts, 57 studies were included. The prevalence of receiving assistance with injection initiation (help or guidance at the first injection) ranged 74% to 100% (n = 13 estimates). The prevalence of ever providing assistance with injection initiation varied widely (range, 13%-69%; n = 13 estimates). Injecting norms, sex/gender, and other correlates classified within Rhodes' social risk environment were commonly associated with providing and receiving assistance. Nearly all PWID receive guidance about injecting for the first time, whereas fewer PWID report providing assistance. Substantial clinical and statistical heterogeneity between studies precluded meta-analysis, and thus local-level estimates may be necessary to guide the implementation of future psychosocial and sociostructural interventions. Further, estimates of providing assistance may be downwardly biased because of social desirability factors.

Self-perception of assisting with future injection drug initiation: The influence of relationships in the process of drug injecting initiation

INTRODUCTION AND AIMS

People who inject drugs (PWID) play critical roles in assisting others into injection drug use (IDU) initiation. Understanding perceptions of PWID's risk of initiating others is needed to inform interventions for prevention. The objective was to examine factors associated with self-perception of assisting with future IDU initiation events. The primary variables of interest are the relationships of PWID with the person(s) they assisted and their reasons for previously providing initiation assistance.

DESIGN AND METHODS

Data from Preventing Injecting by Modifying Existing Responses, a multi-site prospective community-recruited cohort study, were analysed. Analyses were restricted to PWID who reported ever providing IDU initiation assistance. Site-specific (Vancouver, Canada [n = 746]; San Diego, USA [n = 95] and Tijuana, Mexico [n = 92]) multivariable logistic regression analyses were performed to determine factors associated with self-perception of assisting with future IDU initiation.

RESULTS

Having provided IDU initiation assistance to a family member or intimate partner decreased the odds of self-perception of assisting with future IDU initiation in Vancouver (AOR = 0.4; 95% CI 0.2-0.8); however, previous IDU initiation assistance to an 'other' increased the odds of self-perception of assisting with future IDU in Tijuana (AOR = 12.0; 95% CI 2.1-70.3). Daily IDU (Vancouver: AOR = 3.7; 95% CI 2.1-6.4) and less than daily IDU (San Diego: AOR = 5.9; 95% CI 1.3-27.1) (Vancouver: AOR = 2.6; 95% CI 1.4-2.9) were associated with increased self-perception of assisting with future IDU compared to current non-injectors.

DISCUSSION AND CONCLUSIONS

Relationship to past initiates and IDU frequency might increase PWID's self-perception of assisting with future IDU. Interventions focused on social support and reducing IDU frequency may decrease occurrences of IDU initiation assistance.

Recent incarceration and risk of first-time injection initiation assistance: A prospective cohort study of persons who inject drugs

BACKGROUND

Given the prevalence and harms of incarceration among persons who inject drugs (PWID) and their role in injection drug use initiation, we aimed to investigate whether recent incarceration influences the likelihood PWID assist others in their first-ever injection.

METHODS

Prospective cohort study of PWID in Vancouver, Canada who had their PReventing Injecting by Modifying Existing Responses (PRIMER) baseline visit between December 2014 and May 2017, reported never providing injection initiation assistance previously, and had ≥1 follow-up visit. The primary outcome, provision of injection initiation assistance, was defined via self-report as helping anybody inject for the first time in the past six months. The primary exposure was recent incarceration, i.e., self-report of being jailed, imprisoned or detained in the past six months. Participants were assessed biannually until November 2017, drop-out, or their first report of the primary outcome.

RESULTS

1,199 PWID (62.1% male; mean (SD) age, 44.4 (12.3) years) were included in our study. Across 4,171 follow-up visits, 67 participants (5.6%) reported providing injection initiation assistance. The proportion of participants reporting recent incarceration varied between 2.4% to 5.1% per follow-up visit. Based on a multivariable discrete-time proportional hazards regression analysis, recent incarceration was associated with an increased risk of providing injection initiation assistance during the same six-month period (adjusted hazard ratio, 2.64; 95% CI, 1.19 to 5.86).

CONCLUSIONS

The observed association between recent incarceration and risk of providing injection initiation assistance suggests that incarceration could be contributing to the expansion of injection drug use practices within vulnerable populations over time.

When and how do individuals transition from regular drug use to injection drug use in Uganda? Findings from a rapid assessment

BACKGROUND

In Uganda, injection drug use is a growing but less studied problem. Preventing the transition to injection drug use may help prevent blood-borne viral transmission, but little is known about when and how people transition to injection drug use. A greater understanding of this transition process may aid in the country's efforts to prevent the continued growth of injection drug use, HIV, and hepatitis C Virus (HCV) infection among people who inject drugs (PWID).

METHODS

Using a rapid situation assessment framework, we conducted semi-structured interviews among 125 PWID (102 males and 23 females)-recruited through outreach and snow-ball sampling. Participants were interviewed about their experiences on when and how they transitioned into injection drug use and these issues were also discussed in 12 focus groups held with the participants.

RESULTS

All the study participants started their drug use career with non-injecting forms including chewing, smoking, and sniffing before transitioning to injecting. Transitioning was generally described as a peer-driven and socially learnt behavior. The participants' social networks and accessibility to injectable drugs on the market and among close friends influenced the time lag between first regular drug use and first injecting-which took an average of 4.5 years. By the age of 24, at least 81.6% (95.7% for females and 78.4% for males) had transitioned into injecting. Over 84.8% shared injecting equipment during their first injection, 47.2% started injecting because a close friend was already injecting, 26.4% desired to achieve a greater "high" (26.4%) which could reflect drug-tolerance, and 12% out of curiosity.

CONCLUSIONS

Over 81% non-injecting drug users in Kampala and Mbale districts transitioned into injecting by the age of 24; a process that reproduces a population of PWID but also puts them at increased risk of HIV and HCV infection. As Uganda makes efforts to introduce and/or strengthen harm reduction services, interventions targeting non-injecting drug users before they transition into injecting should be considered as a key component for HIV/HCV epidemic control efforts, and their evaluation considered in future researches.

Application of data mining techniques and logistic regression to model drug use transition to injection: a case study in drug use treatment centers in Kermanshah Province, Iran

BACKGROUND

Drug injection has been increasing over the past decades all over the world. Hepatitis B and C viruses (HBV and HCV) are two common infections among people who inject drugs (PWID) and more than 60% of new human immunodeficiency virus (HIV) cases are PWID. Thus, investigating risk factors associated with drug use transition to injection is essential and was the aim of this research.

METHODS

We used a database from drug use treatment centers in Kermanshah Province (Iran) in 2013 that included 2098 records of people who use drugs (PWUD). The information of 29 potential risk factors that are commonly used in the literature on drug use was selected. We employed four classification methods (decision tree, neural network, support vector machine, and logistic regression) to determine factors affecting the decision of PWUD to transition to injection.

RESULTS

The average specificity of all models was over 84%. Support vector machine produced the highest specificity (0.9). Also, this model showed the highest total accuracy (0.91), sensitivity (0.94), positive likelihood ratio [1] and Kappa (0.94) and the smallest negative likelihood ratio (0). Therefore, important factors according to the support vector machine model were used for further interpretation.

CONCLUSIONS

Based on the support vector machine model, the use of heroin, cocaine, and hallucinogens were identified as the three most important factors associated with drug use transition injection. The results further indicated that PWUD with the history of prison or using drug due to curiosity and unemployment are at higher risks. Unemployment and unreliable sources of income were other suggested factors of transition in this research.

Childhood abuse as a risk factor for injection drug use: A systematic review of observational studies

ISSUES

Childhood abuse is a public health challenge with lifelong impacts, including future drug use. However, previous research has been mixed regarding impacts on injection drug use. This systematic review examines the impact of childhood abuse (sexual, physical and emotional) on adult injection drug use.

APPROACH

We searched MEDLINE, EMBASE, PsycINFO, CINAHL, Web of Science and grey literature to identify relevant studies from database inception to 26 September 2018. Studies were eligible if: (i) they were empirical original research published in English; (ii) considered childhood abuse as potential risk factors for lifetime history of injection drug use; and (iii) included adult participants. Risk of bias was assessed using the modified Newcastle-Ottawa Scale.

KEY FINDINGS

Of the 1994 articles screened, 17 studies met the inclusion criteria. Most studies were conducted in the USA and utilised cross-sectional research designs. All of the 17 studies measured sexual abuse, six studies measured physical abuse and three studies measured emotional abuse; most (N = 11) of which reported a statistically significant and positive association between at least one sub-scale of childhood abuse and injection drug use.

IMPLICATIONS

Our findings highlight the need for devising interventions to reduce the harms associated with childhood abuse.

CONCLUSIONS

The evidence base suggests a significant positive association between experiences of childhood physical abuse and elevated risks of injection drug initiation with mixed results for sexual and emotional abuse.

Opioid agonist treatment scale-up and the initiation of injection drug use: A dynamic modeling analysis

BACKGROUND

Injection drug use (IDU) is associated with multiple health harms. The vast majority of IDU initiation events (in which injection-naïve persons first adopt IDU) are assisted by a person who injects drugs (PWID), and as such, IDU could be considered as a dynamic behavioral transmission process. Data suggest that opioid agonist treatment (OAT) enrollment is associated with a reduced likelihood of assisting with IDU initiation. We assessed the association between recent OAT enrollment and assisting IDU initiation across several North American settings and used dynamic modeling to project the potential population-level impact of OAT scale-up within the PWID population on IDU initiation.

METHODS AND FINDINGS

We employed data from a prospective multicohort study of PWID in 3 settings (Vancouver, Canada [n = 1,737]; San Diego, United States [n = 346]; and Tijuana, Mexico [n = 532]) from 2014 to 2017. Site-specific modified Poisson regression models were constructed to assess the association between recent (past 6 month) OAT enrollment and history of ever having assisted an IDU initiation with recently assisting IDU initiation. Findings were then pooled using linear mixed-effects techniques. A dynamic transmission model of IDU among the general population was developed, stratified by known factors associated with assisting IDU initiation and relevant drug use behaviors. The model was parameterized to a generic North American setting (approximately 1% PWID) and used to estimate the impact of increasing OAT coverage among PWID from baseline (approximately 21%) to 40%, 50%, and 60% on annual IDU initiation incidence and corresponding PWID population size across a decade. From Vancouver, San Diego, and Tijuana, respectively, 4.5%, 5.2%, and 4.3% of participants reported recently assisting an IDU initiation, and 49.4%, 19.7%, and 2.1% reported recent enrollment in OAT. Recent OAT enrollment was significantly associated with a 45% lower likelihood of providing recent IDU initiation assistance among PWID (relative risk [RR] 0.55 [95% CI 0.36-0.84], p = 0.006) compared to those not recently on OAT. Our dynamic model predicts a baseline mean of 1,067 (2.5%-97.5% interval [95% I 490-2,082]) annual IDU initiations per 1,000,000 individuals, of which 886 (95% I 406-1,750) are assisted by PWID. Based on our observed statistical associations, our dynamic model predicts that increasing OAT coverage from approximately 21% to 40%, 50%, or 60% among PWID could reduce annual IDU initiations by 11.5% (95% I 2.4-21.7), 17.3% (95% I 5.6-29.4), and 22.8% (95% I 8.1-36.8) and reduce the PWID population size by 5.4% (95% I 0.1-12.0), 8.2% (95% I 2.2-16.9), and 10.9% (95% I 3.2-21.8) relative to baseline, respectively, in a decade. Less impact occurs when the protective effect of OAT is diminished, when a greater proportion of IDU initiations are unassisted by PWID, and when average IDU career length is longer. The study's main limitations are uncertainty in the causal pathway between OAT enrollment and assisting with IDU initiation and the use of a simplified model of IDU initiation.

CONCLUSIONS

In addition to its known benefits on preventing HIV, hepatitis C virus (HCV), and overdose among PWID, our modeling suggests that OAT scale-up may also reduce the number of IDU initiations and PWID population size.

Implementing an Updated "Break the Cycle" Intervention to Reduce Initiating Persons into Injecting Drug Use in an Eastern European and a US "opioid epidemic" Setting

We tested the hypothesis that an updated "Break the Cycle" (BtC) intervention, based in social cognitive theory and motivational interviewing, would reduce the likelihood that current persons who inject drugs (PWID) would assist persons who do not inject drugs (non-PWID) with first injections in Tallinn, Estonia and Staten Island, New York City. 402 PWID were recruited, a baseline interview covering demographics, drug use, and assisting non-PWID with first drug injections was administered, followed by BtC intervention. 296 follow-up interviews were conducted 6 months post-intervention. Percentages assisting with first injections declined from 4.7 to 1.3% (73% reduction) in Tallinn (p < 0.02), and from 15 to 6% (60% reduction) in Staten Island (p < 0.05). Persons assisted with first injections declined from 11 to 3 in Tallinn (p = 0.02) and from 32 to 13 in Staten Island. (p = 0.024). Further implementation research on BtC interventions is urgently needed where injecting drug use is driving HIV/HCV epidemics and areas experiencing opioid epidemics.

Acceptability of safe drug consumption spaces among people who inject drugs in rural West Virginia

Aim

Safe consumption spaces (SCS) are indoor environments in which people can use drugs with trained personnel on site to provide overdose reversal and risk reduction services. SCS have been shown to reduce fatal overdoses, decrease public syringe disposal, and reduce public drug consumption. Existing SCS research in the USA has explored acceptability for the hypothetical use of SCS, but primarily among urban populations of people who inject drugs (PWID). Given the disproportionate impact of the opioid crisis in rural communities, this research examines hypothetical SCS acceptability among a rural sample of PWID in West Virginia.

Methods

Data were drawn from a 2018 cross-sectional survey of PWID (n = 373) who reported injection drug use in the previous 6 months and residence in Cabell County, West Virginia. Participants were asked about their hypothetical use of a SCS with responses dichotomized into two groups, likely and unlikely SCS users. Chi-square and t tests were conducted to identify differences between likely and unlikely SCS users across demographic, substance use, and health measures.

Results

Survey participants were 59.5% male, 83.4% non-Hispanic White, and 79.1% reported likely hypothetical SCS use. Hypothetical SCS users were significantly (p < .05) more likely to have recently (past 6 months) injected cocaine (38.3% vs. 25.7%), speedball (41.0% vs. 24.3%), and to report preferring drugs containing fentanyl (32.5% vs. 20.3%). Additionally, likely SCS users were significantly more likely to have recently experienced an overdose (46.8% vs. 32.4%), witnessed an overdose (78.3% vs. 60.8%), and received naloxone (51.2% vs. 37.8%). Likely SCS users were less likely to have borrowed a syringe from a friend (34.6% vs. 48.7%).

Conclusions

Rural PWID engaging in high-risk behaviors perceive SCS as an acceptable harm reduction strategy. SCS may be a viable option to reduce overdose fatalities in rural communities.

Factors Associated with Frequency of Recent Initiation of Others into Injection Drug Use Among People Who Inject Drugs in Los Angeles and San Francisco, CA, USA, 2016-17

Objective: Drug injection initiation is often assisted by a person who injects drugs (PWID). How often PWID provide this assistance has not been examined. We examine frequency of injection initiation assistance and factors associated with high (4+) and low frequency (1-3) initiation assistance as compared to no initiation assistance among PWID. Methods: Participants were 979 Californian PWID. PWID were interviewed about providing injection initiation assistance in the last 6 months among other items. Multinomial regression analysis was used to examine factors associated with levels of frequency of injection initiation assistance. Results: Among participants, 132 (14%) had initiated 784 people into injection (mean = 5.94 [standard deviation = 20.13]; median = 2, interquartile range = 1,4) in the last 6 months. PWID engaged in high frequency initiation (26% of sample) assisted 662 new initiates (84% of total). Using multinomial regression analysis with no initiating as the referent group, we found that high frequency initiating was statistically associated with higher injection frequency, having a paying sex partner, taking someone to a shooting gallery, and providing injection assistance. Lower frequency initiation was statistically associated with having a paying sex partner, illegal income source, and providing injection assistance. Conclusion: Differences between high and low frequency initiators were not found. Sex work and assisting with drug injection were linked to initiating others. Individual-level interventions that reduce this behavior among PWID and structural interventions such as safe consumption sites and opioid medication treatments that interrupt the social process of injection initiation should be considered as ways to reduce injection initiations.

Navigating social norms of injection initiation assistance during an overdose crisis: A qualitative study of the perspectives of people who inject drugs (PWID) in Vancouver, Canada

Despite the proliferation of fentanyl and fentanyl-adulterated opioids in North America, the impacts of this drug market change on injection initiation processes have not been examined. With the aim of informing structural interventions to address injection initiation and related harms, we explore how people who inject drugs (PWID) in Vancouver, Canada understand and navigate social norms of initiating others into injecting within the context of an overdose crisis. In-depth qualitative interviews were conducted with 19 PWID who reported helping someone inject for the first time. Participants were recruited from two cohort studies of PWID. Participants articulated moral dilemmas about assisting others with injecting. While participants described a 'moral code' prohibiting assisting injection-naïve individuals, this code was not the sole consideration shaping social action around injection initiation. Rather, PWID exercised agency about whether and how to assist novice injectors within the context of constraining and enabling social norms around practicing interpersonal responsibility. Changes to the drug market heightened feelings of moral culpability and criminal liability among PWID who assisted others into injection, given that injecting heightened initiates' risk of overdose. These concerns operated in tension with the aim of protecting novice injectors from harms associated with an increasingly potent and unpredictable drug supply by providing them with injection assistance, education and supervision. Our analysis of how PWID practice interpersonal responsibility helps conceptualise how 'moral codes' prohibiting initiation assistance are managed and negotiated amidst structural vulnerability. Structural interventions reducing the vulnerability of novice injectors should be prioritized, including the implementation of supervised injection sites allowing for assisted injection, Good Samaritan laws, and policy changes conducive to a safer drug supply.

"Another Person Was Going to Do It": The Provision of Injection Drug Use Initiation Assistance in a High-Risk U.S.-Mexico Border Region

Background: Persons who inject drugs (PWID) play a key role in assisting others' initiation into injection drug use (IDU). We aimed to explore the pathways and socio-structural contexts for this phenomenon in Tijuana, Mexico, a border setting marked by a large PWID population with limited access to health and social services. Methods: Preventing Injecting by Modifying Existing Responses (PRIMER) is a multi-cohort study assessing socio-structural factors associated with PWID assisting others into initiating IDU. Semi-structured qualitative interviews in Tijuana included participants ≥18 years old, who reported IDU within the month prior to cohort enrollment and ever initiating others into IDU. Purposive sampling ensured a range of drug use experiences and behaviors related to injection initiation assistance. Thematic analysis was used to develop recurring and significant data categories. Results: Twenty-one participants were interviewed (8 women, 13 men). Broadly, participants considered public injection to increase curiosity about IDU. Many considered transitioning into IDU as inevitable. Emergent themes included providing assistance to mitigate overdose risk and to protect initiates from being taken advantage of by others. Participants described reluctance in engaging in this process. For some, access to resources (e.g., shared drugs or a monetary fee) was a motivator to initiate others. Conclusion: In Tijuana, public injection and a lack of harm reduction services are perceived to fuel the incidence of IDU initiation and to incentivize PWID to assist in injection initiation. IDU prevention efforts should address structural factors driving PWID participation in IDU initiation while including PWID in their development and implementation.

Injection Drug Use Trajectories among Migrant Populations: A Narrative Review

BACKGROUND

Dual epidemics of injection drug use and blood-borne disease, characterized as "syndemics," are present in a range of settings. Behaviors that drive such syndemics are particularly prevalent among mobile drug-using populations, for whom cross-border migration may pose additional risks.

OBJECTIVES

This narrative review aims to characterize the risk factors for injection drug use initiation associated with migration, employing a risk environment framework and focusing on the San Diego-Tijuana border region as the most dynamic example of these phenomena.

METHODS

Based on previous literature, we divide migration streams into three classes: intra-urban, internal, and international. We synthesized existing literature on migration and drug use to characterize how mobility and migration drive the initiation of injection drug use, as well as the transmission of hepatitis and HIV, and to delineate how these might be addressed through public health intervention.

RESULTS

Population mixing between migrants and receiving communities and the consequent transmission of social norms about injection drug use create risk environments for injection drug use initiation. These risk environments have been characterized as a result of local policy environments, injection drug use norms in receiving communities, migration-related stressors, social dislocation, and infringement on the rights of undocumented migrants.

CONCLUSION

Policies that exacerbate risk environments for migrants may inadvertently contribute to the expansion of epidemics of injection-driven blood-borne disease. Successful interventions that address emerging syndemics in border regions may therefore need to be tailored to migrant populations and distinguish between the vulnerabilities experienced by different migration classes and border settings.

A fragmented code: The moral and structural context for providing assistance with injection drug use initiation in San Diego, USA

BACKGROUND

Injection drug use initiation is shaped by social networks and structural contexts, with people who inject drugs often assisting in this process. We sought to explore the norms and contexts linked to assisting others to initiate injection drug use in San Diego, USA, to inform the development of structural interventions to prevent this phenomenon.

METHODS

We undertook qualitative interviews with a purposive sample of people who inject drugs and had reported assisting others to initiate injection (n = 17) and a sub-sample of people who inject drugs (n = 4) who had not reported initiating others to triangulate accounts. We analyzed data thematically and abductively.

RESULTS

Respondents' accounts of providing initiation assistance were consistent with themes and motives reported in other contexts: of seeking to reduce harm to the 'initiate', responding to requests for help, fostering pleasure, accessing resources, and claims that initiation assistance was unintentional. We developed analysis of these themes to explore initiation assistance as governed by a 'moral code'. We delineate a fragmented moral code which includes a range of meanings and social contexts that shape initiation assistance. We also show how assistance is happening within a structural context that limits discussion of injection drug use, reflecting a prevailing silence on drug use linked to stigma and criminalization.

CONCLUSIONS

In San Diego, the assistance of others to initiate injection drug use is governed by a fragmented moral code situated within particular social norms and contexts. Interventions that address the social and structural conditions shaped by and shaping this code may be beneficial, in tandem with efforts to support safe injection and the reduction of injection-related harms.

Non-injection Drug Use and Injection Initiation Assistance among People Who Inject Drugs in Tijuana, Mexico

Although most people who inject drugs (PWID) report receiving assistance during injection initiation events, little research has focused on risk factors among PWID for providing injection initiation assistance. We therefore sought to determine the influence of non-injection drug use among PWID on their risk to initiate others. We used generalized estimating equation (GEE) models on longitudinal data among a prospective cohort of PWID in Tijuana, Mexico (Proyecto El Cuete IV), while controlling for potential confounders. At baseline, 534 participants provided data on injection initiation assistance. Overall, 14% reported ever initiating others, with 4% reporting this behavior recently (i.e., in the past 6 months). In a multivariable GEE model, recent non-injection drug use was independently associated with providing injection initiation assistance (adjusted odds ratio [AOR] = 2.42, 95% confidence interval [CI] = 1.39-4.20). Further, in subanalyses examining specific drug types, recent non-injection use of cocaine (AOR = 9.31, 95% CI = 3.98-21.78), heroin (AOR = 4.00, 95% CI = 1.88-8.54), and methamphetamine (AOR = 2.03, 95% CI = 1.16-3.55) were all significantly associated with reporting providing injection initiation assistance. Our findings may have important implications for the development of interventional approaches to reduce injection initiation and related harms. Further research is needed to validate findings and inform future approaches to preventing entry into drug injecting.

Do law enforcement interactions reduce the initiation of injection drug use? An investigation in three North American settings

BACKGROUND

The prevention of drug injecting is often cited as a justification for the deployment of law enforcement and for the continuation of drug criminalization policies. We sought to characterize the impact of law enforcement interactions on the risk that people who inject drugs (PWID) report assisting others with injection initiation in three North American countries.

METHODS

Cross-sectional data from PWID participating in cohort studies in three cities (San Diego, USA; Tijuana, Mexico; Vancouver, Canada) were pooled (August 2014-December 2016). The dependent variable was defined as recently (i.e., past six months) providing injection initiation assistance; the primary independent variable was the frequency of recent law enforcement interactions, defined categorically (0 vs. 1 vs. 2-5 vs. ≥6). We employed multivariable logistic regression analyses to assess this relationship while controlling for potential confounders.

RESULTS

Among 2122 participants, 87 (4.1%) reported recently providing injection initiation assistance, and 802 (37.8%) reported recent law enforcement interactions. Reporting either one or more than five recent interactions with law enforcement was not significantly associated with injection initiation assistance. Reporting 2-5 law enforcement interactions was associated with initiation assistance (Adjusted Odds Ratio=1.74, 95% Confidence Interval: 1.01-3.02).

CONCLUSIONS

Reporting interactions with law enforcement was not associated with a reduced likelihood that PWID reported initiating others into injection drug use. Instead, we identified a positive association between reporting law enforcement interactions and injection initiation assistance among PWID in multiple settings. These findings raise concerns regarding the effectiveness of drug law enforcement to deter injection drug use initiation.

The experience of initiating injection drug use and its social context: a qualitative systematic review and thematic synthesis

BACKGROUND AND AIM

Understanding the experience of initiating injection drug use and its social contexts is crucial to inform efforts to prevent transitions into this mode of drug consumption and support harm reduction. We reviewed and synthesized existing qualitative scientific literature systematically to identify the socio-structural contexts for, and experiences of, the initiation of injection drug use.

METHODS

We searched six databases (Medline, Embase, PsychINFO, CINAHL, IBSS and SSCI) systematically, along with a manual search, including key journals and subject experts. Peer-reviewed studies were included if they qualitatively explored experiences of or socio-structural contexts for injection drug use initiation. A thematic synthesis approach was used to identify descriptive and analytical themes throughout studies.

RESULTS

From 1731 initial results, 41 studies reporting data from 1996 participants were included. We developed eight descriptive themes and two analytical (higher-order) themes. The first analytical theme focused on injecting initiation resulting from a social process enabled and constrained by socio-structural factors: social networks and individual interactions, socialization into drug-using identities and choices enabled and constrained by social context all combine to produce processes of injection initiation. The second analytical theme addressed pathways that explore varying meanings attached to injection initiation and how they link to social context: seeking pleasure, responses to increasing tolerance to drugs, securing belonging and identity and coping with pain and trauma.

CONCLUSIONS

Qualitative research shows that injection drug use initiation has varying and distinct meanings for individuals involved and is a dynamic process shaped by social and structural factors. Interventions should therefore respond to the socio-structural influences on injecting drug use initiation by seeking to modify the contexts for initiation, rather than solely prioritizing the reduction of individual harms through behavior change.

Acceptability and design preferences of supervised injection services among people who inject drugs in a mid-sized Canadian City

BACKGROUND

Supervised injection services (SIS) have been shown to reduce the public- and individual-level harms associated with injection drug use. While SIS feasibility research has been conducted in large urban centres, little is known about the acceptability of these services among people who inject drugs (PWID) in mid-sized cities. We assessed the prevalence and correlates of willingness to use SIS as well as design and operational preferences among PWID in London, Canada.

METHODS

Between March and April 2016, peer research associates administered a cross-sectional survey to PWID in London. Socio-demographic characteristics, drug-use patterns, and behaviours associated with willingness to use SIS were estimated using bivariable and multivariable logistic regression models. Chi-square tests were used to compare characteristics with expected frequency of SIS use among those willing to use SIS. Design and operational preferences are also described.

RESULTS

Of 197 PWID included in this analysis (median age, 39; interquartile range (IQR), 33-50; 38% female), 170 (86%) reported willingness to use SIS. In multivariable analyses, being female (adjusted odds ratio (AOR) 0.29; 95% confidence interval (CI) 0.11-0.75) was negatively associated with willingness to use, while public injecting in the last 6 months (AOR 2.76; 95% CI 1.00-7.62) was positively associated with willingness to use. Participants living in unstable housing, those injecting in public, and those injecting opioids and crystal methamphetamine daily reported higher expected frequency of SIS use (p < 0.05). A majority preferred private cubicles for injecting spaces and daytime operational hours, while just under half preferred PWID involved in service operations.

CONCLUSIONS

High levels of willingness to use SIS were found among PWID in this setting, suggesting that these services may play a role in addressing the harms associated with injection drug use. To maximize the uptake of SIS, programme planners and policy makers should consider the effects of gender and views of PWID regarding SIS design and operational preferences.

Hepatitis C infection and other drug-related harms among inpatients who injected drugs in Turkey

Hepatitis C virus (HCV) is easily spread among those who share drug injection equipment. Due to the ease of contraction and growing prevalence of HCV in Eastern Europe, the aims of this study focused on describing risky injection practices as well as the prevalence of HCV, HIV and hepatitis B virus (HBV) among people who inject drugs (PWID) who were admitted to public and private drug treatment centres in Turkey from 2012 to 2013. Other aims included identifying correlates of needle sharing and HCV infection. Of the 4694 inpatients who ever injected drugs and the 3914 who injected in the past 30 days, nearly all (98%) reported heroin as their drug of choice, the vast majority reported ever sharing a needle (73.4% and 79.3%), and the mean age at first injection was 23 years. Of current PWID, 51.9% were HCV-positive, 5.9% were HBV-positive and only 0.34% of lifetime PWID were HIV-positive. Predictors of increased needle sharing include younger age, being unemployed, having lesser education and reporting heroin as a drug of choice. Significant predictors of HCV infection included being 40 years or older, receiving treatment in the Mediterranean region of Turkey, reporting heroin as a primary substance, a longer duration of drug use and sharing needles. With this information, it is essential to improve access to clean injection equipment in Turkey, to focus on improving education on clean injection practices and to enhance efforts in testing and treating HCV-positive PWID.

Down in the valley: Trajectories of injection initiation among young injectors in California's Central Valley

BACKGROUND

Injection drug use initiation represents a critical point of public health intervention, as injection increases risk for blood borne infections including Hepatitis C and HIV. In this paper, we explore pathways to injection initiation among youth (≤30) in the rural context of California's Central Valley, where rates of injection drug use are among the highest in the nation.

METHODS

We draw on semi-structured qualitative interviews with 20 young injectors to examine drug use histories, including the factors that participants associated with their transition to injection drug use.

RESULTS

The average age was 24.7 years (range: 20-30), 45% were female (n=9), and 30% were Latino (n=6). Participants described a variety of pathways to injection, culminating in a first injection that involved either opioids (n=12) or methamphetamine (n=8). Among the opioid group, the majority used prescription opioids before transitioning to injection, while a smaller number transitioned to opioid injection from non-opioid recreational drug use. Injectors who first used prescription opioids often described growing up in affluent suburban areas and transitioned to injection with peers, owing to a combination of factors related to individual tolerance, cost, and shifting drug markets. In contrast, methamphetamine initiates grew up in less affluent families with histories of substance use that exposed them to drugs at an early age. Methamphetamine users transitioned from smoking and snorting to injection, often with family members or intimate partners, within broader contexts of social disadvantage and stress.

CONCLUSION

While much of the focus on young injectors has centred on the current opioid epidemic, our data suggest a need to consider multiple pathways towards injection initiation of different drugs. Targeted interventions addressing the unique injection transition contexts of both opioids and methamphetamine are urgently needed in the Central Valley of California.

Characteristics and Patterns of use among Regular Heroin Sniffers

The purpose of this paper is to characterize persons who sniff heroin by examining their experiences prior to first heroin use, experiences at first use, current drug use patterns, and factors associated with progression to the daily use of heroin. Relatively little has been published about the lives and career trajectories of heroin sniffers who have little or no history of drug injection. A sample of 250 African-American, Hispanic/Latino, and non-Hispanic White men and women who sniffed heroin were interviewed for this study. Most people first sniffed heroin in a social setting where heroin use was not preplanned. Heroin sniffing has become a sustained pattern of use for many of these users; the majority have progressed to daily sniffing of heroin and are polydrug users for whom crack is an important substance; and heroin sniffers have experienced a range of life and health problems including a high prevalence of HIV.

Baseline HCV Antibody Prevalence and Risk Factors among Drug Users in China's National Methadone Maintenance Treatment Program

BACKGROUND

Hepatitis C virus (HCV) is the most common viral infection among injecting drug users worldwide. We aimed to assess HCV antibody prevalence and associated risk factors among clients in the Chinese national methadone maintenance treatment (MMT) program.

METHODS

Data from 296,209 clients who enrolled in the national MMT program between March 2004 and December 2012 were analyzed to assess HCV antibody prevalence, associated risk factors, and geographical distribution.

RESULTS

Anti-HCV screening was positive for 54.6% of clients upon MMT entry between 2004 and 2012. HCV antibody prevalence at entry declined from 66.8% in 2005 to 45.9% in 2012. The most significant predictors of HCV seropositivity were injecting drug use (adjusted odds ratio [AOR]: 8.34, 95% confidence interval [CI]: 8.17-8.52, p<0.0001) and a history of drug use ≥9 years (AOR: 2.01, 95% CI: 1.96-2.06, p<0.0001). Being female, of Uyghur or Zhuang ethnicity, and unmarried were identified as demographic risk factors (all p-values<0.0001). Of the 28 provincial-level divisions included in the study, we found that 5 divisions had HCV antibody prevalence above 70% and 20 divisions above 50%. The HCV screening rate within 6 months after MMT entry greatly increased from 30.4% in 2004 to 93.1% in 2012.

CONCLUSIONS

The current HCV antibody prevalence remains alarmingly high among MMT clients throughout most provincial-level divisions in China, particularly among injecting drug users and females. A comprehensive prevention strategy is needed to control the HCV epidemic among MMT clients in China.

Individual and Neighborhood Characteristics Associated with HIV Among Black and Latino Adults Who Use Drugs and Unaware of Their HIV-Positive Status, New York City, 2000-2004

With mounting evidence of how neighborhood socioeconomic context influences individual behavior, investigation of neighborhood social context and sex/drug use risk behavior could help explain and provide insight into solutions to solve persistent racial disparities in HIV. Interviewer-administered surveys and HIV testing among street-recruited individuals who reported illicit drug use in New York City were conducted from 2000 to 2004. Individuals were geocoded to census tracts, and generalized estimating equations were used to determine correlates of being newly diagnosed with HIV at study enrollment. Analyses were completed in 2014. Of the 920 participants, 10.5 % were HIV-positive, and among those, 45 % were diagnosed at study enrollment. After restricting the sample to those who self-reported negative HIV status (n = 867), 72 % were male, 65 % Latino, and 5.1 % tested HIV-positive. After adjustment, those testing HIV-positive were more likely to report male same-sex partnership (p < 0.01) and less likely to be homeless compared with those confirmed HIV-negative (p < 0.01). Neighborhood-adjusted models indicated those from neighborhoods with less deprivation (p < 0.05), and a higher proportion of owner-occupied homes (p < 0.01) were more likely to test HIV-positive. Additionally, Black individuals who used drugs and were from neighborhoods with a higher proportion of Black residents were more likely to be newly diagnosed compared to Latino individuals who used drugs and were from neighborhoods with lower proportions of Black residents (p < 0.05). These data suggest that HIV prevention and treatment efforts should continue widening its reach to those unaware of their HIV infection, namely men who have sex with men, heavy, drug-involved Black communities, and both Black and Latino communities from relatively less disadvantaged neighborhoods.

Transition to injecting drug use in Iran: A systematic review of qualitative and quantitative evidence

BACKGROUND

Injection drug use, a behavior associated with significant adverse health effects, has been increasing over the past decade in Iran. This study aims to systematically review the epidemiological and qualitative evidence on factors that facilitate or protect the transition to injection drug use in Iran.

METHODS

We conducted electronic searches in five international (Medline, Web of Science, EMBASE, CINAHL, PsycINFO), one regional (IMEMR) and three Iranian (Iranmedex, Iranpsych, IranDoc) databases, as well as contacting experts in the field. Two trained researchers screened documents to identify relevant studies and independently dual-extracted data following pre-specified protocol. We applied principles of thematic analysis for qualitative data and applied a random effect meta-analysis model for age of first injection.

RESULTS

A total of 38 documents from 31 studies met eligibility criteria, from which more than 50% were implemented from 2006 to 2008. The weighted mean age of first injection was 25.8 (95% Confidence Interval: 25.3-26.2). Between 1998 and 2011, the age of first injection was relatively stable. Overall, drug users had used drugs for 6-7 years before they started injection use. Heroin was the first drug of injection in the majority of the cases. We identified factors influencing the initiation of or transition to injection use at various levels, including: (1) individual (pleasure-seeking behavior, curiosity and development of drug dependency commonly reported), (2) social and environmental (role of peer drug users in the first injection use, the economic efficiency associated with injections and the wide availability of injectable form of drugs in the market).

CONCLUSION

Harm reduction policies in Iran have almost exclusively focused on drug injectors in Iran. However, given the extent of the non-injection drug use epidemic, evidence from this study can provide insight on points of interventions for the prevention of the transition to injection use.

Potential bias due to outcome-related loss to follow-up in cohort studies on incidence of drug injection: systematic review and meta-analysis

AIMS

A systematic review and meta-analysis were conducted to synthesize results from cohort studies on initiation into drug injection among vulnerable populations, to quantify heterogeneity in the estimated incidence rates of drug injection and to identify potential sources of heterogeneity and bias.

METHODS

MEDLINE, EMBASE, PsycINFO and LILACS were searched for relevant studies published between 1980 and 2012. Investigators independently reviewed studies for inclusion, retrieved information on baseline population characteristics and follow-up features and assessed study quality. Study-specific incidence rates of drug injection were calculated as the number of new injectors divided by the person-years at risk. The I(2) statistic was used to quantify heterogeneity in incidence rates across studies, and random-effects meta-regression models were used to identify determinants of heterogeneity and bias.

RESULTS

Nine cohorts totalling 1843 participants met the inclusion criteria, with individual sample sizes of 70-415 participants and follow-up lengths of 6 months-3.4 years. The incidence of drug injection varied widely, from 2.1 to 24.2 cases per 100 person-years. The strong between-study heterogeneity (I(2)  = 90%, P<0.001) was reduced significantly after accounting for the different follow-up lengths (I(2)  = 17%, P = 0.30), with a 57% (95% confidence interval 46-66%) decrease in the pooled incidence of drug injection per 1-year increase in average follow-up.

CONCLUSIONS

The incidence of drug injection decreases sharply with increasing follow-up length in cohort studies on drug injection initiation. Low retention rates and potential for downward selection bias in cohort studies on drug injection initiation are caused primarily by greater loss to follow-up among individuals at higher risk of starting injection, compared with other participants.

Experiences of and attitudes toward injecting drug use among marginalized African migrant and refugee youth in Melbourne, Australia

Little is known about injecting drug use (IDU) among people from culturally and linguistically diverse backgrounds in Australia. We interviewed 18 young people of African ethnicity (6 current/former injectors, 12 never injectors) about exposure and attitudes to IDU. Exposure to IDU was common, with IDU characterized as unnatural, risky and immoral. IDU was highly stigmatized and hidden from family and friends. There is a need for culturally appropriate programs to promote open dialogue about substance use to reduce stigma and prevent African youth who may use illicit drugs from becoming further marginalized.

Development of a brief substance use sensation seeking scale: validation and prediction of injection-related behaviors

Sensation seeking, a personality trait, has been shown to predict engagement in high-risk behaviors. However, little is known regarding the impact of sensation seeking on substance use among street youth. We therefore sought to modify a sensation seeking scale (SSS) for use among this population. Street youth from the Vancouver-based At-Risk Youth Study (n = 226) completed the modified SSS. Exploratory and confirmatory factor analysis (EFA/CFA) were undertaken to establish the scale's dimensionality and internal validity. The association between SSS score and injection-related behaviors was tested using generalized estimating equation analysis. EFA results indicated scale unidimensionality. The comparative fit index (CFI) suggested acceptable fit (CFI = 0.914). In multivariate analysis, sensation seeking was independently associated with injection drug use, crystal methamphetamine use, polysubstance use, and binge drug use (all p < 0.05). Our findings provide preliminary support for the use of the modified SSS among street youth.

How do drug market changes affect characteristics of injecting initiation and subsequent patterns of drug use? Findings from a cohort of regular heroin and methamphetamine injectors in Melbourne, Australia

BACKGROUND

Changes in drug market characteristics have been shown to affect drug use patterns but few studies have examined their impacts on injecting initiation experiences and subsequent patterns of injecting drug use (IDU).

METHODS

We collected data on self-reported injecting initiation experiences and past-month patterns of IDU from 688 regular heroin and methamphetamine injectors in Melbourne, Australia, who initiated injecting across three different drug market periods (prior to the Australian heroin shortage ('high heroin')/immediately following the shortage ('low heroin')/'contemporary' markets (fluctuating heroin and methamphetamine availability)). We used univariable and multivariable logistic regression to examine the relationship between period of injecting initiation and first drug injected, and multinomial logistic regression for the relationship between period of injecting initiation and current injecting patterns.

RESULTS

425 participants (62%) reported initiating injecting in the high heroin period, 146 (21%) in the low heroin period, and 117 (17%) in the contemporary period. Participants who initiated injecting during the low heroin period were twice as likely to initiate injecting using a drug other than heroin (AOR: 1.94, 95% CI: 1.27-2.95). The most common patterns of drug use among study participants in the month preceding interview were polydrug use (44%) and primary heroin use (41%). Injecting initiation period was either non-significantly or weakly associated with current drug use pattern, which was more strongly associated with other socio-demographic and drug use characteristics, particularly self-reported drug of choice.

CONCLUSION

The drug market period in which injecting initiation occurred influenced the first drug injected and influenced some aspects of subsequent drug use. In the context of highly dynamic drug markets in which polydrug use is common there is a need for broad harm reduction and drug treatment services which are flexible and responsive to changing patterns of drug use.

Community Impact of Pharmacy-Randomized Intervention to Improve Access to Syringes and Services for Injection Drug Users

OBJECTIVES

In an effort to reduce HIV transmission among injection drug users (IDUs), New York State deregulated pharmacy syringe sales in 2001 through the Expanded Syringe Access Program by removing the requirement of a prescription. With evidence suggesting pharmacists' ability to expand their public health role, a structural, pharmacy-based intervention was implemented to determine whether expanding pharmacy practice to include provision of HIV risk reduction and social/medical services information during the syringe sale would (a) improve pharmacy staff attitudes toward IDUs (b) increase IDU syringe customers, and (c) increase prescription customer base in New York City neighborhoods with high burden of HIV and illegal drug activity.

METHODS

Pharmacies (n = 88) were randomized into intervention (recruited IDU syringe customers into the study and delivered intervention activities), primary control (recruited IDU syringe customers only) and secondary control (did not recruit IDUs or deliver intervention activities) arms.

RESULTS

Pharmacy staff in the intervention versus secondary control pharmacies showed significant decreases in the belief that selling syringes to IDUs causes community loitering.

CONCLUSIONS

Structural interventions may be optimal approaches for changing normative attitudes about highly stigmatized populations.

Prevalence of HIV infection and risk behaviors among younger and older injecting drug users in the United States, 2009

This study compared HIV sero-prevalence and risk behaviors between younger and older injecting drug users (IDUs). IDUs aged ≥18 years were interviewed for the 2009 National HIV Behavioral Surveillance System. Using GEE regression, we assessed characteristics of younger (18-29 years) and older (≥30 years) IDUs, and factors associated with past 12-month receptive syringe sharing and unprotected sex (vaginal/anal). Of 10,090 participants, 10 % were younger. HIV sero-prevalence was lower among younger than older IDUs (4 vs. 10 %, p = 0.001). Younger IDUs were more likely (p ≤ 0.002) to be non-black race/ethnicity, report higher household income, homelessness, being arrested and to engage in receptive syringe sharing and unprotected sex. In multivariable models, age remained associated (p < 0.001) with receptive syringe sharing (aPR = 1.14, 95 % CI1.07-1.22) and unprotected sex (aPR = 1.10, 95 % CI1.06-1.14). Although younger IDUs had lower HIV prevalence, their behaviors place them at increased risk of HIV infection and could lead to a rapid spread in this susceptible population.

The multiple truths about crystal meth among young people entrenched in an urban drug scene: a longitudinal ethnographic investigation

Transitions into more harmful forms of illicit drug use among youth have been identified as important foci for research and intervention. In settings around the world, the transition to crystal methamphetamine (meth) use among youth is considered a particularly dangerous and growing problem. Epidemiological evidence suggests that, particularly among young, street-involved populations, meth use is associated with numerous sex- and drug-related "risks behaviors" and negative health outcomes. Relatively few studies, however, have documented how youth themselves understand, experience and script meth use over time. From 2008 to 2012, we conducted over 100 in-depth interviews with 75 street-entrenched youth in Vancouver, Canada, as well as ongoing ethnographic fieldwork, in order to examine youth's understandings and experiences of meth use in the context of an urban drug scene. Our findings revealed positive understandings and experiences of meth in relation to other forms of drug addiction and unaddressed mental health issues. Youth were simultaneously aware of the numerous health-related harms and social costs associated with heavy meth use. Over time, positive understandings of meth may become entirely contradictory to a lived reality in which escalating meth use is a factor in further marginalizing youth, although this may not lead to cessation of use. Recognition of these multiple truths about meth, and the social structural contexts that shape the scripting of meth use among youth in particular settings, may help us to move beyond moralizing debates about how to best educate youth on the "risks" associated with meth, and towards interventions that are congruent with youth's lived experiences and needs across the lifecourse.

Health and social harms associated with crystal methamphetamine use among street-involved youth in a Canadian setting

BACKGROUND AND OBJECTIVES

Despite recent increases in crystal methamphetamine use among high-risk populations such as street-involved youth, few prospective studies have examined the health and social outcomes associated with active crystal methamphetamine use.

METHODS

We enrolled 1,019 street-involved youth in Vancouver, Canada, in a prospective cohort known as the at-risk youth study (ARYS). Participants were assessed semi-annually and a generalized estimating equation (GEE) logistic regression was used to identify factors independently associated with active crystal methamphetamine use.

RESULTS

Among 1,019 participants recruited into ARYS between 2005 and 2012 the median follow up duration was 17 months, 320 (31.4%) participants were female and 454 (44.6%) had previously used crystal methamphetamine at baseline. In adjusted GEE analyses, active crystal methamphetamine use was independently associated with Caucasian ethnicity (adjusted odds ratio [AOR] = 1.37; 95% confidence interval [CI]: 1.04-1.81), homelessness (AOR = 1.34; 95% CI: 1.15-1.56), injection drug use (AOR = 3.40; 95% CI: 2.76-4.19), non-fatal overdose (AOR = 1.46; 95%CI: 1.07-2.00), being a victim of violence (AOR = 1.19; 95% CI: 1.02-1.38), involvement in sex work (AOR = 1.39; 95% CI: 1.03-1.86), and drug dealing (AOR = 1.60; 95% CI: 1.35-1.90).

DISCUSSION AND CONCLUSIONS

Prevalence of crystal methamphetamine use was high in this setting and active use was independently associated with a range of serious health and social harms.

SCIENTIFIC SIGNIFICANCE

Evidence-based strategies to prevent and treat crystal methamphetamine use are urgently needed.

Crystal methamphetamine and initiation of injection drug use among street-involved youth in a Canadian setting

BACKGROUND

Although injection drug use is known to result in a range of health-related harms, including transmission of HIV and fatal overdose, little is known about the possible role of synthetic drugs in injection initiation. We sought to determine the effect of crystal methamphetamine use on risk of injection initiation among street-involved youth in a Canadian setting.

METHODS

We used Cox regression analyses to identify predictors of injection initiation among injection-naive street-involved youth enrolled in the At-Risk Youth Study, a prospective cohort study of street-involved youth in Vancouver, British Columbia. Data on circumstances of first injection were also obtained.

RESULTS

Between October 2005 and November 2010, a total of 395 drug injection-naive, street-involved youth provided 1434 observations, with 64 (16.2%) participants initiating injection drug use during the follow-up period, for a cumulative incidence of 21.7 (95% confidence interval [CI] 1.7-41.7) per 100 person-years. In multivariable analysis, recent noninjection use of crystal methamphetamine was positively associated with subsequent injection initiation (adjusted hazard ratio 1.93, 95% CI 1.31-2.85). The drug of first injection was most commonly reported as crystal methamphetamine (14/31 [45%]).

INTERPRETATION

Noninjection use of crystal methamphetamine predicted subsequent injection initiation, and crystal methamphetamine was the most commonly used drug at the time of first injection. Evidence-based strategies to prevent transition to injection drug use among crystal methamphetamine users are urgently needed.

Interventions to prevent the initiation of injection drug use: a systematic review

BACKGROUND

Injection drug use has been identified as a key source of morbidity and mortality, primarily from overdose and the transmission of blood-borne diseases such as HIV. Experts have therefore called for the prioritization of resources toward the prevention of injection drug use. However, these strategies have not been systematically assessed.

METHODS

PRISMA guidelines were used to systematically review and extract findings from the peer-reviewed literature evaluating the effectiveness of interventions to prevent injecting initiation. We searched 10 English language electronic databases (PubMed, PsycINFO, EMBASE, Cochrane CENTRAL, CINAHL, Web of Science, TOXNET, AIDSLINE, AMED and ERIC), the Internet (Google, Google Scholar), and article reference lists, from database inception to June 1st, 2012.

RESULTS

Overall, out of 384 studies identified in the initial search, eight met the inclusion criteria. Studies evaluated four different types of interventions: social marketing, peer-based behavior modification, treatment, and drug law enforcement. Four studies observed a significant effect of the intervention on reducing rates of injecting initiation. Peer-based behavior modification and addiction treatment interventions were found to be most effective. Two of three studies assessing the impact of drug law enforcement on patterns of injecting initiation found no impact on injecting initiation, while one study reported inconclusive results.

CONCLUSION

There exists a limited scientific literature on strategies to prevent injecting initiation. Resources should be allocated toward increased research and development of effective interventions to prevent this phenomenon.

Risk factors for progression to regular injection drug use among street-involved youth in a Canadian setting

BACKGROUND

Street-involved youth are at high risk for experimenting with injection drug use; however, little attention has been given to identifying the factors that predict progression to on-going injecting.

METHODS

Logistic regression was used to identify factors associated with progression to injecting weekly on a regular basis among a Canadian cohort of street-involved youth.

RESULTS

Among our sample of 405 youth who had initiated injecting at baseline or during study observation, the median age was 22 years (interquartile range [IQR]=21-24), and 72% (293) reported becoming a regular injector at some point after their first injection experience. Of these, the majority (n=186, 63%) reported doing so within a month of initiating injection drug use. In multivariate analysis, the drug used at the first injection initiation event (opiates vs. cocaine vs. methamphetamine vs. other; all p>0.05) was not associated with progression; however, younger age at first injection (adjusted odds ratio [AOR]=1.13), a history of childhood physical abuse (AOR=1.81), prior regular use of the drug first injected (AOR=1.77), and having a sexual partner present at the first injection event (AOR=2.65) independently predicted progression to regular injecting.

CONCLUSION

These data highlight how quickly youth progress to become regular injectors after experimentation. Findings indicate that addressing childhood trauma and interventions such as evidence-based youth focused addiction treatment that could prevent or delay regular non-injection drug use, may reduce progression to regular injection drug use among this population.

Trends in the population prevalence of people who inject drugs in US metropolitan areas 1992-2007

BACKGROUND

People who inject drugs (PWID) have increased risk of morbidity and mortality. We update and present estimates and trends of the prevalence of current PWID and PWID subpopulations in 96 US metropolitan statistical areas (MSAs) for 1992-2007. Current estimates of PWID and PWID subpopulations will help target services and help to understand long-term health trends among PWID populations.

METHODOLOGY

We calculated the number of PWID in the US annually from 1992-2007 and apportioned estimates to MSAs using multiplier methods. We used four types of data indicating drug injection to allocate national annual totals to MSAs, creating four distinct series of component estimates of PWID in each MSA and year. The four component estimates are averaged to create the best estimate of PWID for each MSA and year. We estimated PWID prevalence rates for three subpopulations defined by gender, age, and race/ethnicity. We evaluated trends using multi-level polynomial models.

RESULTS

PWID per 10,000 persons aged 15-64 years varied across MSAs from 31 to 345 in 1992 (median 104.4) to 34 to 324 in 2007 (median 91.5). Trend analysis indicates that this rate declined during the early period and then was relatively stable in 2002-2007. Overall prevalence rates for non-Hispanic black PWID increased in 2005 as compared to other racial/ethnic groups. Hispanic prevalence, in contrast, declined across time. Importantly, results show a worrisome trend in young PWID prevalence since HAART was initiated--the mean prevalence was 90 to 100 per 10,000 youth in 1992-1996, but increased to >120 PWID per 10,000 youth in 2006-2007.

CONCLUSIONS

Overall, PWID rates remained constant since 2002, but increased for two subpopulations: non-Hispanic black PWID and young PWID. Estimates of PWID are important for planning and evaluating public health programs to reduce harm among PWID and for understanding related trends in social and health outcomes.

Injection of drug residue as a potential risk factor for HCV acquisition among Montréal young injection drug users

BACKGROUND

Preparing drugs or medications for injection may leave residues in containers and filters used by injection drug users (IDUs). Little is known about the specific practice of injecting someone else's drug residue as a possible route of HCV transmission.

METHODS

A prospective cohort study of street youth aged 14-23 years old was carried out between July 2001 and December 2005. For this analysis, youth who injected in the six months prior to interview were selected if they were HCV-negative and had completed at least one follow-up visit. Semi-annual visits involved completing an interviewer-administered questionnaire and providing a blood sample for HCV antibody testing. "Sharing behaviors" (any injection preparation behavior that could entail IDUs using injection equipment used by others) including injecting someone else's drug residue were assessed at each interview. Predictors of HCV seroconversion were identified using Cox proportional hazards regression analyses. Two multivariate models were built, one considering sharing behaviors only, and one with cocaine injection forced into it.

RESULTS

Of the 175 participants, 60% were male and their mean age was 20.7years old. In both models, residue injection was a predictor of HCV incidence, although with marginal statistical significance. The adjusted hazard ratio estimates were (2.15; 95% CI 0.99-4.67) and (2.11; 95% CI 0.97-4.62) respectively.

CONCLUSION

This epidemiological study underscores the role injection of drug residue may play in HCV transmission among IDUs. In the current context of the worldwide HCV epidemics, this question deserves further investigation.

Correlates and contexts of US injection drug initiation among undocumented Mexican migrant men who were deported from the United States

Preventing the onset of injection drug use is important in controlling the spread of HIV and other blood borne infections. Undocumented migrants in the United States face social, economic, and legal stressors that may contribute to substance abuse. Little is known about undocumented migrants' drug abuse trajectories including injection initiation. To examine the correlates and contexts of US injection initiation among undocumented migrants, we administered quantitative surveys (N = 309) and qualitative interviews (N = 23) on migration and drug abuse experiences to deported male injection drug users in Tijuana, Mexico. US injection initiation was independently associated with ever using drugs in Mexico pre-migration, younger age at first US migration, and US incarceration. Participants' qualitative interviews contextualized quantitative findings and demonstrated the significance of social contexts surrounding US injection initiation experiences. HIV prevention programs may prevent/delay US injection initiation by addressing socio-economic and migration-related stressors experienced by undocumented migrants.

Estimates of the population prevalence of injection drug users among hispanic residents of large US metropolitan areas

Little information exists on the population prevalence or geographic distribution of injection drug users (IDUs) who are Hispanic in the USA. Here, we present yearly estimates of IDU population prevalence among Hispanic residents of the 96 most populated US metropolitan statistical areas (MSAs) for 1992-2002. First, yearly estimates of the proportion of IDUs who were Hispanic in each MSA were created by combining data on (1) IDUs receiving drug treatment services in Substance Abuse and Mental Health Services Administration (SAMHSA)'s Treatment Entry Data System, (2) IDUs being tested in the Centers for Disease Control and Prevention (CDC) HIV-Counseling and Testing System, and (3) incident AIDS diagnoses among IDUs, supplemented by (4) data on IDUs who were living with AIDS. Then, the resulting proportions were multiplied by published yearly estimates of the number of IDUs of all racial/ethnic groups in each MSA to produce Hispanic IDU population estimates. These were divided by Hispanic population data to produce population prevalence rates. Time trends were tested using mixed-effects regression models. Hispanic IDU prevalence declined significantly on average (1992 mean = 192, median = 133; 2002 mean = 144, median = 93; units are per 10,000 Hispanics aged 15-64). The highest prevalence rates across time tended to be in smaller northeastern MSAs. Comparing the last three study years to the first three, prevalence decreased in 82% of MSAs and increased in 18%. Comparisons with data on drug-related mortality and hepatitis C mortality supported the validity of the estimates. Generally, estimates of Hispanic IDU population prevalence were higher than published estimates for non-Hispanic White residents and lower than published estimates for non-Hispanic Black residents. Further analysis indicated that the proportion of IDUs that was Hispanic decreased in 52% and increased in 48% of MSAs between 2002 and 2007. The estimates resulting from this study can be used to investigate MSA-level social and economic factors that may have contributed to variations across MSAs and to help guide prevention program planning for Hispanic IDUs within MSAs. Future research should attempt to determine to what extent these trends are applicable to Hispanic national origin subgroups.

Progress in HIV reduction and prevention among injection and noninjection drug users

Substantial progress has been made in reducing HIV among injection drug users (IDUs) in the United States, despite political and social resistance that reduced resources and restricted access to services. The record for HIV prevention among noninjecting drug users is less developed, although they are more numerous than IDUs. Newer treatments for opiate and alcohol abuse can now be integrated into primary HIV care; treatment for stimulant abuse is less developed. All drug users present challenges for newer HIV prevention strategies (eg, "test and treat," nonoccupational postexposure prophylaxis and preexposure prophylaxis, contingency management, and conditional cash transfer). A comprehensive HIV prevention program that includes multicomponent multilevel approaches (ie, individual, network, structural) has been effective in HIV prevention among IDUs. Expanding these approaches to noninjecting drug users, especially those at highest risk (eg, minority men who have sex with men) and incorporating these newer approaches is a public health priority.

Initiation to drug injection among street youth: a gender-based analysis

OBJECTIVE(S)

To estimate the incidence rate of initiation into drug injection and to identify predictors of initiation into drug injection separately among street girls and boys.

DESIGN

Data from two consecutive prospective street youth cohort studies (1995-2001 and 2001-2005) were used to conduct these analyses, stratified by gender.

METHODS

Data were collected using semi-annual interviewer-administered questionnaires. Variables from the following domains were considered in Cox regression models: socio-demographic characteristics, early and current substance abuse, marginalization, childhood traumatic sexual events and injection exposure.

RESULTS

Of the 946 youth who had never injected drugs at study entry, 86.4% completed at least two questionnaires representing 243 girls and 574 boys. Incidence rates of injection of 7.0 and 5.9 per 100 person-years were observed among these girls and boys respectively. Among girls, cocaine or crack use (adjusted hazard ratio (AHR)=1.97), heroin use (AHR=2.86), homelessness (AHR=2.49) and hanging out regularly with people who inject (AHR=4.46) all independently increased risk of first injection. Among boys, age decreased risk of initiating injection (AHR=0.90/year), while cocaine or crack use (AHR=2.14), heroin use (AHR=3.56), homelessness before age 16 (AHR=1.68), incest or rape before age 14 (AHR=1.98) and hanging out regularly with people who inject (AHR=1.66) all independently increased this risk.

CONCLUSIONS

Our findings suggest similar rates of initiation among girls and boys; however, factors associated with initiation vary by gender. This might lead to the design of more effective programs to prevent initiation into drug injection.