M2HepPrEP: study protocol for a multi-site multi-setting randomized controlled trial of integrated HIV prevention and HCV care for PWID.

BACKGROUND: Opioid use is escalating in North America and comes with a multitude of health consequences, including HIV and hepatitis C virus (HCV) outbreaks among persons who inject drugs (PWID). HIV pre-exposure prophylaxis (PrEP) and HCV treatment regimens have transformative potential to address these co-occurring epidemics. Evaluation of innovative multi-modal approaches, integrating harm reduction, opioid agonist therapy (OAT), PrEP, and HCV treatment is required. The aim of this study is to assess the effectiveness of an on-site integrated care model where delivery of PrEP and HCV treatment for PWID takes places at syringe service programs (SSP) and OAT programs compared with referring PWID to clinical services in the community through a patient navigation model and to examine how structural factors interact with HIV prevention adherence and HCV treatment outcomes. METHODS: The Miami-Montreal Hepatitis C and Pre-Exposure Prophylaxis trial (M2HepPrEP) is an open-label, multi-site, multi-center, randomized, controlled, superiority trial with two parallel treatment arms. A total of 500 persons who injected drugs in the prior 6 months and are eligible for PrEP will be recruited in OAT clinics and SSP in Miami, FL, and Montréal, Québec. Participants will be randomized to either on-site care, with adherence counseling, or referral to off-site clinics assisted by a patient navigator. PrEP will be offered to all participants and HCV treatment to those HCV-infected. Co-primary endpoints will be (1) adherence to pre-exposure prophylaxis medication at 6 months post-randomization and (2) HCV sustained virological response (SVR) 12 weeks post-treatment completion among participants who were randomized within the HCV stratum. Up to 100 participants will be invited to participate in a semi-structured interview regarding perceptions of adherence barriers and facilitators, after their 6-month assessment. A simulation model-based cost-effectiveness analysis will be performed to determine the comparative value of the strategies being evaluated. DISCUSSION: The results of this study have the potential to demonstrate the effectiveness and cost-effectiveness of offering PrEP and HCV treatment in healthcare venues frequently attended by PWID. Testing the intervention in two urban centers with high disease burden among PWID, but with different healthcare system dynamics, will increase generalizability of findings. TRIAL REGISTRATION: Clinicaltrials.gov NCT03981445 . Trial registry name: Integrated HIV Prevention and HCV Care for PWID (M2HepPrEP). Registration date: June 10, 201.

Technology-Based Psychological Interventions for Young Adults With Early Psychosis and Cannabis Use Disorder: Qualitative Study of Patient and Clinician Perspectives.

BACKGROUND: The persistence of cannabis use disorder (CUD) in young adults with first-episode psychosis (FEP) is associated with poor clinical and functional outcomes. Face-to-face psychological interventions are effective in treating CUD. However, their use in early intervention services (EISs) for psychosis is inconsistent because of barriers, including high workload and heterogeneity in training of clinicians and lack of motivation for treatment among patients. Tailoring new technology-based psychological interventions (TBPIs) to overcome these barriers is necessary to ensure their optimal acceptability. OBJECTIVE: The aim of this study is twofold: to explore psychological intervention practices and intervention targets that are relevant for treating CUD in individuals with early psychosis and to explore factors related to the development and implementation of a technology-assisted psychological intervention. METHODS: A total of 10 patients undergoing treatment for FEP and CUD in EISs participated in a focus group in June 2019. Semistructured individual interviews were conducted with 10 clinicians working in first-episode clinics in the province of Québec, Canada. A hybrid inductive-deductive approach was used to analyze data. For the deductive analysis, we used categories of promoting strategies found in the literature shown to increase adherence to web-based interventions for substance use (ie, tailoring, reminders, delivery strategies, social support, and incentives). For the inductive analysis, we identified new themes through an iterative process of reviewing the data multiple times by two independent reviewers. RESULTS: Data were synthesized into five categories of factors that emerged from data collection, and a narrative synthesis of commonalities and differences between patient and clinician perspectives was produced. The categories included attitudes and beliefs related to psychological interventions (eg, behavioral stage of change), strategies for psychological interventions (eg, motivational interviewing, cognitive behavioral therapy, psychoeducation, stress management), incentives (eg, contingency management), general interest in TBPIs (eg, facilitators and barriers of TBPIs), and tailoring of TBPIs (eg, application needs and preferences, outcome measures of interest for clinicians). CONCLUSIONS: This study provides a comprehensive portrait of the multifaceted needs and preferences of patients and clinicians related to TBPIs. Our results can inform the development of smartphone- or web-based psychological interventions for CUD in young adults with early psychosis.

Painful lives: Chronic pain experience among people who use illicit drugs in Montreal (Canada).

The current opioid crisis in North America has strengthened the boundary between "genuine chronic pain patients" and "drug addicts," though these categories are not mutually exclusive. Despite its high prevalence -more than double the general population rate- chronic pain among people who use illicit drugs (PWUD) remains an overlooked issue in both health and social sciences. Using the theoretical framework of sociology of illness experience, the aim of this qualitative study was to understand how the experience of illicit drug use shapes the chronic pain experience. We conducted in-depth interviews with 25 individuals who used street opioids and/or cocaine (with or without any other drug) and had suffered from chronic pain for three months or more. Participants were recruited from July 2017 to May 2018, in Montreal (Canada). Social deprivation and drug use increased PWUD's exposure to a wide range of health issues including chronic pain. Even when intense, pain was often described as peripheral in their life given their many other problems. They experienced double stigmatization due to the cumulation of two socially devalued statuses, "drug addicts" and "chronic pain sufferers." Their attempts to avoid stigma included valuing their toughness/endurance and pursuing physical activities despite the pain. Some reported using substances like cocaine or heroin to meet social expectations of performance regardless of pain. This study improves the knowledge on illness experiences within deprived social settings by showing how marginalization and stigma render PWUD's pain clinically and socially invisible.

Chronic pain management among people who use drugs: A health policy challenge in the context of the opioid crisis.

BACKGROUND: In Canada, the rise in prescription opioid (PO) overdoses and addiction is a major public health concern. Various health authorities have recently recommended that physicians use caution when prescribing opioids, especially to people with histories of substance use. As a result, fewer therapeutic options are available for people who use drugs (PWUD) and suffer from chronic non-cancer pain (CNCP). This paper examines how PWUD describe their experiences with CNCP management in the context of the opioid crisis. METHODS: This qualitative study is based on in-depth interviews with Montreal (Canada) PWUD experiencing CNCP for 3 months or more. RESULTS: Most of the 25 participants (27-61 years; 10 women, 15 men) were polysubstance users (cocaine, opioids, amphetamine, etc.) suffering from CNCP for several years, with multiple additional health and social problems. The majority were unsatisfied with their CNCP management. They felt labelled as "addicts" and stigmatized within the healthcare system. Many participants had been denied PO, even those with severe CNCP and those who were not opioid-dependent. Participants expressed a desire to access non-pharmacological CNCP therapies, but these were often too expensive. Some PWUD were offered methadone to relieve CNCP and found this inappropriate. As a last resort several participants reported self-medicating CNCP with street drugs, increasingly known to be laced with fentanyl. CONCLUSION: PWUD with CNCP are affected by two opioid crises: the PO crisis and the street-opioid crisis. The lack of a coherent policy that addresses their pain management produces reoccurring problems when seeking CNCP relief. Restrictive prescription measures implemented in response to the PO crisis may have consequences similar to prohibitionist policies: they heighten overdose risks for PWUD by increasing exposure to street drugs laced with fentanyl. Improving access to diverse CNCP management options for PWUD can help reduce harms related to street-opioid use.

The evolving drug epidemic of prescription opioid injection and its association with HCV transmission among people who inject drugs in Montréal, Canada.

AIMS: To examine temporal trends in prescription opioid (PO) injection and to assess its association with hepatitis C virus (HCV) seroconversion among people who inject drugs (PWID). DESIGN: Prospective cohort study spanning 2004 to 2016. SETTING: Montréal, Canada. PARTICIPANTS: PWID reporting injection during the past 6 months. MEASUREMENTS: PWID were recruited between 2004 and 2016. At each 3-6-month follow-up visit, participants completed interview-administered questionnaires and were tested for HCV-antibody. FINDINGS: Among 1524 PWID [83% males, mean age 38 years, standard deviation (SD) = 10, 34% (31-36) prescription opioid (PO) injection past month] included in trends analyses, PO injection use expanded between 2004 and 2009, and plateaued between 2010 and 2016 (trend tests < 0.001 and 0.335, respectively). Of the 432 HCV-seronegative PWIDs followed at least once (81% males, mean age 34, SD 9.8, 38% injection PO), 153 became HCV-antibody-positive during 1230 years of follow-up, for an incidence of 12.4 per 100 person-years [95% confidence interval (CI) = 10.6, 14.6]. PO injectors were 3.9 times more likely to seroconvert to HCV, relative to non-PO injectors. In a multivariate analysis, a stronger association between PO injection and HCV seroconversion was found post-2009 [adjusted hazard ratio (aHR) = 5.4, 95% CI = 2.7, 10.8] than before (aHR = 1.5, 95% CI = 0.9, 2.4) (P-value for interaction = 0.001). CONCLUSION: Prescription opioid injection increased among people who inject drugs in Montréal, Canada from 2004 to 2009, to reach a plateau between 2010 and 2016. The association between prescription opioid injection and HCV seroconversion was stronger during the second period than the first according to the epidemic phase.

Tranquilizer misuse among active cocaine users: Predictors of initiation.

INTRODUCTION AND AIMS: Tranquilizer use is associated with negative health outcomes among people who use drugs. This paper aims to estimate the incidence rate (initiation) and identify predictors of tranquilizer misuse (TM) among cocaine users. DESIGN AND METHODS: A prospective cohort study was conducted in Montreal, Canada. Interviewer-administered questionnaires were carried out at 3-month intervals. Initiation was defined as misusing a tranquilizer for the first time during follow-up. 'Lasting-initiation', defined as reporting TM at the next visit following first use, was also examined. Cox proportional hazard regression analyses were carried out to assess predictors of initiation to TM. RESULTS: Among the 245 participants who were eligible for the initiation analyses, 123 started TM during follow-up for an incidence rate of 40.49 per 100 person-years (95% confidence interval, CI: 33.80-48.15). Of the 123 initiates, 35.7% were still using at the interview following initiation for an incidence rate of 14.70 per 100 person-years (95% CI: 10.82-19.56). Multivariate models showed that independent predictors of initiation and 'lasting initiation' were identical as having had a criminal activity as the main source of income, having been recently in treatment for a substance use disorder (SUD) and reporting non-medical use of prescription opioids. DISCUSSION AND CONCLUSIONS: The incidence rate of TM initiation was high among a sample of cocaine users. Initiation was predicted by a problematic drug use pattern involving polydrug use, involvement in the street economy and having been in treatment for a SUD. These findings have implications for prevention and harm reduction strategies.

Examining the Association Between Psychiatric Disorders and Cocaine Binges: Results From the COSMO Study.

OBJECTIVES: Although cocaine binges and mental health problems have both been identified as significant risk factors for different health hazards, little is known about the relationship between mental health and cocaine binging. Hence, the aim of this study is to examine the association between psychiatric disorders and cocaine binge. METHODS: Participants were part of a prospective cohort study of individuals who either smoke or inject cocaine. The dependent variable, namely a cocaine binge within the past month, was defined as the repetitive use of large quantities of cocaine until the individual was unable to access more of the drug or was physically unable to keep using. Psychiatric disorders were assessed using the Composite International Diagnostic Interview and the Diagnostic Interview Schedule questionnaires. Logistic regression models were performed to examine the association between cocaine binging and psychiatric disorders, adjusting for potential confounders. RESULTS: Of the 492 participants, 24.4% reported at least 1 cocaine binging episode during the prior month. Among the study population, 48.0% met the criteria for antisocial personality disorder (ASPD), 45.5% for anxiety disorders, and 28.2% for mood disorders. Participants with ASPD were more likely to binge (adjusted odds ratio 1.73, 95% confidence interval 1.10-2.73), whereas those with a mood disorder were not. The association between anxiety disorders and cocaine binging was significant only in univariate analyses. CONCLUSION: ASPD increased the odds of reporting cocaine binge in our study population. These results highlight the need for a better understanding of the specific dimensions of ASPD that contribute to the increased risk of unsafe drug use behaviors.

"I love having benzos after my coke shot": The use of psychotropic medication among cocaine users in downtown Montreal.

BACKGROUND: Cocaine abuse is a major public health issue due to its role in the HIV and hepatitis C virus (HCV) epidemics in North America. A significant area of concern among people who use cocaine (PWUC), injected or smoked, is their frequent misuse of prescription drugs, particularly psychotropic medication (PM), such as tranquilizers, sedatives, stimulants, and antipsychotics. This paper aims to describe and understand practices of PM use among PWUC in downtown Montreal. METHOD: Ethnographic methods including participant observation and semi-structured interviews were used in an iterative manner. RESULTS: Two thirds of the 50 participants were male. They ranged in age from 20 to 60 and most were homeless. A significant proportion of them reported polydrug use patterns that included frequent concomitant opioid use (heroin and/or prescription opioids (PO)). Benzodiazepine-based tranquilizers and the atypical antipsychotic quetiapine were the most frequently used PM. Routes of PM administration were oral, nasal and, to a lesser degree, intravenous. Five main PM use practices were identified: 1) "downers" from cocaine high (benzodiazepines and quetiapine); 2) enhancers of heroin/PO effects (benzodiazepines); 3) reducers or suppressors of heroin/PO withdrawal symptoms (benzodiazepines); 4) enablers of a different type of "trip" (benzodiazepines); and 5) treatment for mental and physical problems (benzodiazepines and quetiapine). CONCLUSION: PM use practices showed several complementary functions that PM fulfill in a context of polydrug use. The soothing and stimulating effects of PM reinforce the patterns of drug use among participants, posing various risks including overdose, HIV/HCV transmission, PM dependence and accidents. The results highlight the need for clinicians to assess clients' substance use patterns when prescribing PM and to question PWUC about PM use. The findings also underline certain unmet service needs in relation to overdose, HIV/HCV and mental health prevention/treatment among cocaine users.

Drug use practices among people who inject drugs in a context of drug market changes: Challenges for optimal coverage of harm reduction programs.

BACKGROUND: Until the early 2000s, people who inject drugs (PWID) in Québec had mainly been injecting powder cocaine and heroin. Since then, ethnographic studies have shown that the drug market has diversified, with crack and prescription opioids (PO) becoming increasingly available. This could have led to changes in drug use practices among PWID. The objectives of our study were to examine annual trends in injection of different drugs, crack smoking and frequent injection (FI), as well as relationships between injected drugs and FI. METHODS: PWID are participants in the ongoing Québec SurvUDI surveillance system. PWID (past 6 months) were recruited in 2 urban and 6 semi-urban/rural sites. Each visit included a structured interview addressing drug use behaviours. Analyses were carried out using GEE methods. For trend analyses (2003-2014) on drugs and FI (number of injections≥upper quartile, previous month), the first annual interview was selected for PWID with multiple participations per year. Analyses on associations between FI and types of injected drugs were based on all interviews (2004-2014). RESULTS: Crack/cocaine and heroin injection declined significantly, with prevalence ratios (PR) per year of 0.983 [95% confidence interval (CI): 0.980-0.986] and 0.979 (95% CI: 0.969-0.990), while PO injection [PR=1.052 (1.045-1.059)], crack smoking [PR=1.006 (1.001-1.012)], and FI (≥120 injections, previous month) significantly increased [PR=1.015 (1.004-1.026)]. Compared to PWID who injected crack/cocaine±other drugs, the proportion of PWID reporting FI was higher among those who injected PO+heroin/speedball, crack/cocaine or other drugs (adjusted PR 2.29; 95% CI: 2.07-2.53) or PO only (aPR 1.72; 95%CI: 1.47-2.01). CONCLUSIONS: Changes that have occurred in the drug market are reflected in PWID's practices. The high frequency of injection observed among PO injectors is of particular concern. Drug market variations are a challenge for health authorities responsible for harm reduction programs.

Examining the link between cocaine binging and individual, social and behavioral factors among street-based cocaine users.

AIMS: To estimate the prevalence of cocaine binging and examine associated factors, to characterize binge episodes and to study the relationship between cocaine binging and HIV and HCV risk behaviors among street-based cocaine users. METHODS: A prospective cohort study was conducted in Montréal, Canada. Interviewer-administered questionnaire were carried out at 3-month intervals. Cocaine binging was defined as using large quantities of cocaine, without stopping, over a limited period of time, until resources run out or until being physically incapable of consuming. Generalized Estimation Equations (GEE) analyses were used. Covariates considered included demographic, behavioral, mental health and social risk factors. FINDINGS: In total, 605 participants were recruited. Prevalence of cocaine binging over the month prior to recruitment was 24.5%. Correlates of cocaine binging were older age (AOR 1.46), homelessness (AOR 1.44), criminal/marginal income strategies (AOR 1.61), high psychological distress (AOR 1.31), high cocaine dependence (AOR 3.71), drug overdoses (AOR 1.56) and smoking as the main route of cocaine administration (AOR 1.38). Additional GEE analyses showed that cocaine binging was significantly associated with the sharing of drug paraphernalia (AOR 1.35) and sexual relations under the influence of cocaine (AOR 1.21). CONCLUSION: Cocaine binging is frequent among street-based cocaine users and is associated with markers of vulnerability. It is also associated with increased odds of both sexual and drug use risk behaviors. Interventions need to be tailored in order to help cocaine bingers develop personal strategies that could prevent binging. Harm reduction programs should help cocaine bingers adequately assess their drug equipment needs.

Prevalence and correlates of prescription opioid residue injection.

BACKGROUND: There is growing evidence of intravenous administration of prescription opioids (POs) in several countries. Preparation of POs for injection may leave residues in containers and filters used by people who inject drugs and may lead to adverse health outcomes if they are injected. METHODS: This exploratory study used cross-sectional data from the COSMO study, a prospective cohort of out-of-treatment cocaine users carried out in Montréal (Canada) between October 2010 and August 2015. For this analysis, only one visit per participant was selected, that is, the first time the participant reported PO injection during the study. The outcome of interest, "injection of PO residues", was defined as having injected PO residues from a filter and/or a container in the last month. Correlates of this outcome were identified using logistic regression analyses. RESULTS: Of the 122 participants who reported PO injection during the study period, 41.8% had injected PO residues. Reporting an unstable source of income (AOR=4.26; 95% CI: 1.03-17.69), a recent overdose (AOR=5.45; 95% CI: 1.50-19.88) and a preponderant use of opiates (mostly opiate use versus other drugs excluding alcohol and cannabis) (AOR=2.46; 95% CI: 1.08-5.63) increased the risk of PO residue injection. The odds of reporting PO residue injection rose by 7% per unit increase in the score of psychological distress (AOR=1.07 per unit increase; 95% CI: 1.01-1.12). CONCLUSIONS: The findings of this study suggest that PO residue injection is associated with markers of vulnerability. Further investigation is needed in order to better understand this understudied drug injection practice.

Epidemiology of Injection Drug Use: New Trends and Prominent Issues.

After more than 30 years of research, numerous studies have shown that injection drug use is associated with a wide range of adverse health outcomes such as drug overdoses, drug-related suicidal behaviours, comorbid psychiatric disorders, bloodborne pathogens and other infectious diseases, and traumas. This review explores new trends and prominent issues associated with injection drug use. The dynamic nature of injection drug use is underlined by examining its recent trends and changing patterns in Canada and other "high-income countries." Three research topics that could further contribute to the development of comprehensive prevention and intervention strategies aimed at people who inject drugs are also discussed: risk behaviours associated with the injection of prescription opioids, binge injection drug use, and mental health problems as determinants of injection risk behaviours.

Exploration of a crack use setting and its impact on drug users' risky drug use and sexual behaviors: the case of piaules in a Montréal neighborhood.

From July 2011, a one-year study based on ethnographic methodology was carried out in "crack houses" in the neighborhood of Hochelaga-Maisonneuve in Montréal, Canada. The study aimed to explore the operational style of a specific indoor drug use setting and its impact on users' risky sexual and drug use behaviors in a context of drug market change. A thematic analysis of observational and interview notes was conducted. This study stresses the importance to examine the role of environmental factors in relation to crack smoking's health-related risks and to complement individual-based interventions with structural strategies. The study's limitations are noted.

Estimating the size of the population of persons who inject drugs in the island of Montréal, Canada, using a six-source capture-recapture model.

BACKGROUND: To plan and implement services to persons who inject drugs (PWID), knowing their number is essential. For the island of Montréal, Canada, the only estimate, of 11,700 PWID, was obtained in 1996 through a capture-recapture method. Thirteen years later, this study was undertaken to produce a new estimate. METHODS: PWID were defined as individuals aged 14-65 years, having injected recently and living on the island of Montréal. The study period was 07/01/2009 to 06/30/2010. An estimate was produced using a six-source capture-recapture log-linear regression method. The data sources were two epidemiological studies and four drug dependence treatment centres. Model selection was conducted in two steps, the first focusing on interactions between sources and the second, on age group and gender as covariates and as modulators of interactions. RESULTS: A total of 1480 PWID were identified in the six capture sources. They corresponded to 1132 different individuals. Based on the best-fitting model, which included age group and sex as covariates and six two-source interactions (some modulated by age), the estimated population was 3910 PWID (95% confidence intervals (CI): 3180-4900) which represents a prevalence of 2.8 (95% CI: 2.3-3.5) PWID per 1000 persons aged 14-65 years. CONCLUSIONS: The 2009-2010 estimate represents a two-third reduction compared to the one for 1996. The multisource capture-recapture method is useful to produce estimates of the size of the PWID population. It is of particular interest when conducted at regular intervals thus allowing for close monitoring of the injection phenomenon.

Prevalence and temporal trends of crack injection among injection drug users in eastern central Canada.

BACKGROUND: Little is known about crack injection and its temporal trends in North America. This article describes the extent of crack injection and examines temporal trends among injection drug users (IDUs) recruited from 2003 to 2010 in the SurvUDI network. METHODS: IDUs who injected recently (past 6 months) were recruited in harm reduction and health programs in eastern central Canada. Trend analyses were performed using generalized estimating equations. Some IDUs participated multiple times; first interview was retained for the descriptive analyses, while first interview per year was retained for the trend analyses. RESULTS: Of the 4088 IDUs recruited, 15.2% (621) reported crack injection; large variations across sites were noted (range: 0.3-39.5%). Trend analyses were limited to Ottawa (449 crack injectors) and Montréal (121). For Ottawa, a significant decline was observed, from 48.3% to 36.9%, with a prevalence ratio (PR) of 0.97 per year (95% CI: 0.94-0.99). For Montréal, a significant rise was observed, from 6.0% to 18.4%, with a PR of 1.29 per year (95% CI: 1.19-1.40). CONCLUSIONS: Strong variations in crack injection exist throughout the SurvUDI network, and reversed temporal trends have been observed in Ottawa and Montréal. These data will be useful to local harm reduction programs to evaluate the need to distribute items required by crack injectors and to develop prevention messages.

Patterns of cocaine and opioid co-use and polyroutes of administration among street-based cocaine users in Montréal, Canada.

BACKGROUND: Effective public health programs aimed at problematic cocaine users are challenged by the fact that they can have complex patterns of drug use with respect to polysubstance use and routes of drug administration. This study was carried out to explore the presence of subgroups of cocaine users on the basis of their concurrent use of opioids and their routes of cocaine and opioid administration, and to determine if subgroups could be differentiated in terms of sociodemographic factors and risk behaviours. METHODS: Regular cocaine users (≥1 per week) were recruited in low-threshold services located in the Montréal downtown area. The following variables were examined: demographic characteristics, types of drug used, routes of drug administration, and condom use with occasional or commercial sexual partners. Latent class analysis and multinomial logistic regression modeling were carried out. RESULTS: 886 cocaine users were recruited (83.5% male: mean age 35.38 years). A 5-class model was identified: (1) "cocaine smokers" (CSs) (n = 161; membership probability (MP) = 0.183); (2) "cocaine smokers/sniffers" (CSSs) (n = 201; MP = 0.218); (3) "cocaine injectors" (CIs) (n = 207; MP = 0.231); (4) "cocaine-opioid injectors" (COIs) (n = 277; MP = 0.291); (5) "cocaine-opioid polyroute users" (COPs) (n = 40; MP = 0.077). Compared with COIs, other subtypes were significantly different in terms of either age, duration of cocaine use, ethnic background, homelessness, polydrug use or condom use. CONCLUSION: The heterogeneity of consumption patterns supports the importance of offering an array of interventions aimed at problematic cocaine users. These should include the provision of clean injecting and smoking material, the promotion of safe sexual behaviours and the prevention of initiation to drug injection. In the absence of specific treatment, cocaine users should have access to primary health care services and addiction treatment based on innovative behavioural and pharmacological approaches.

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.

The rising prevalence of prescription opioid injection and its association with hepatitis C incidence among street-drug users.

AIMS: To examine trends in prescription opioid (PO) injection and to assess its association with hepatitis C virus (HCV) seroconversion among injection drug users (IDUs). DESIGN: Prospective cohort study. SETTING: Montreal, Canada. PARTICIPANTS: HCV-negative IDUs at baseline, reporting injection in the past month. MEASUREMENTS: Semi-annual visits included HCV antibody testing and an interview-administered questionnaire assessing risk behaviours. HCV incidence rate was calculated using the person-time method. Time-updated Cox regression models were conducted to examine predictors of HCV incidence. FINDINGS: The proportion of IDUs reporting PO injection increased from 21% to 75% between 2004 and 2009 (P < 0.001). Of the 246 participants (81.6% male; mean age 34.5 years; mean follow-up time 23 months), 83 seroconverted to HCV [incidence rate: 17.9 per 100 person-years; 95% confidence interval (CI) 14.3, 22.1]. Compared to non-PO injectors, PO injectors were more likely to become infected [adjusted hazard ratio (AHR): 1.87; 95%CI:1.16, 3.03]. An effect modification was also found: PO injectors who did not inject heroin were more likely to become infected (AHR: 2.88; 95%CI: 1.52, 5.45) whereas no association was found for participants using both drugs (AHR: 1.19; 95% CI: 0.61, 2.30). Other independent predictors of HCV incidence were: cocaine injection, recent incarceration and >30 injections per month. CONCLUSIONS: Prescription opioid injectors who do not inject heroin are at greater risk for HCV seroconversion than are those injecting both heroin and prescription opioids. Important differences in age, behaviour and social context suggest a need for targeted outreach strategies to this population.