Using an intersectionality lens to explore barriers and enablers to hepatitis C point-of-care testing: a qualitative study among people who inject drugs and service providers.

BACKGROUND: Hepatitis C virus (HCV) infection is a significant global health burden, particularly among people who inject drugs. Rapid point-of-care HCV testing has emerged as a promising approach to improve HCV detection and linkage to care in harm reduction organizations such as needle and syringe programs. The objective of this study was to use an intersectionality lens to explore the barriers and enablers to point-of-care HCV testing in a needle and syringe program. METHODS: A qualitative study was conducted using semi-structured interviews with clients (people who inject drugs) and service providers in a large community organization focused on the prevention of sexually transmitted and blood borne infections and harm reduction in Montreal, Canada. An intersectionality lens was used alongside the Theoretical Domains Framework to guide the formulation of research questions as well as data collection, analysis, and interpretation. RESULTS: We interviewed 27 participants (15 clients, 12 providers). For clients, four themes emerged: (1) understanding and perceptions of HCV testing, (2) the role of an accessible and inclusive environment, (3) the interplay of emotions and motivations in decision-making, and (4) the impact of intersectional stigma related to HCV, behaviors, and identities. For providers, five themes emerged: (1) knowledge, skills, and confidence for HCV testing, (2) professional roles and their intersection with identity and lived experience, (3) resources and integration of services, (4) social and emotional factors, and (5) behavioral regulation and incentives for HCV testing. Intersectional stigma amplified access, emotional and informational barriers to HCV care for clients. In contrast, identity and lived experience acted as powerful enablers for providers in the provision of HCV care. CONCLUSION: The application of an intersectionality lens provides a nuanced understanding of multilevel barriers and enablers to point-of-care HCV testing. Findings underscore the need for tailored strategies that address stigma, improve provider roles and communication, and foster an inclusive environment for equitable HCV care. Using an intersectionality lens in implementation research can offer valuable insights, guiding the design of equity-focused implementation strategies.

The impact of the COVID-19 pandemic on people who use drugs in three Canadian cities: a cross-sectional analysis.

BACKGROUND: The COVID-19 pandemic had a disproportionate impact on the health and wellbeing of people who use drugs (PWUD) in Canada. However less is known about jurisdictional commonalities and differences in COVID-19 exposure and impacts of pandemic-related restrictions on competing health and social risks among PWUD living in large urban centres. METHODS: Between May 2020 and March 2021, leveraging infrastructure from ongoing cohorts of PWUD, we surveyed 1,025 participants from Vancouver (n = 640), Toronto (n = 158), and Montreal (n = 227), Canada to describe the impacts of pandemic-related restrictions on basic, health, and harm reduction needs. RESULTS: Among participants, awareness of COVID-19 protective measures was high; however, between 10 and 24% of participants in each city-specific sample reported being unable to self-isolate. Overall, 3-19% of participants reported experiencing homelessness after the onset of the pandemic, while 20-41% reported that they went hungry more often than usual. Furthermore, 8-33% of participants reported experiencing an overdose during the pandemic, though most indicated no change in overdose frequency compared the pre-pandemic period. Most participants receiving opioid agonist therapy in the past six months reported treatment continuity during the pandemic (87-93%), however, 32% and 22% of participants in Toronto and Montreal reported missing doses due to service disruptions. There were some reports of difficulty accessing supervised consumption sites in all three sites, and drug checking services in Vancouver. CONCLUSION: Findings suggest PWUD in Canada experienced difficulties meeting essential needs and accessing some harm reduction services during the COVID-19 pandemic. These findings can inform preparedness planning for future public health emergencies.

Determinants of psychological distress during the COVID-19 pandemic among people who use drugs in Montreal, Canada.

INTRODUCTION: Limited data exists on psychological impacts of the COVID-19 pandemic among people who use drugs (PWUD). This study aimed to determine the prevalence and correlates of severe psychological distress (PD) among PWUD in Montreal around the beginning of the pandemic. METHODS: We conducted a rapid assessment study from May to December 2020 among PWUD recruited via a community-based cohort of people who inject drugs in Montreal (Hepatitis C cohort [HEPCO], N = 128) and community organisations (N = 98). We analysed self-reported data on changes in drug use behaviours and social determinants since the declaration of COVID-19 as a public health emergency, and assessed past-month PD using the Kessler K6 scale. Multivariable logistic regression was conducted to examine correlates of PD distress (score ≥13). RESULTS: Of 226 survey participants, a quarter (n = 56) were screened positive for severe PD. In multivariable analyses, age (1-year increment) (adjusted odds ratio = 0.94, 95% confidence interval [0.90, 0.98]) and a decrease in non-injection drug use versus no change (0.26 [0.07, 0.92]) were protective against severe PD, while positive associations were found for any alcohol use in the past 6 months (3.73 [1.42, 9.78]), increased food insecurity (2.88 [1.19, 6.93]) and both moving around between neighbourhoods more (8.71 [2.63, 28.88]) and less (3.03 [1.18, 7.74]) often compared to no change. DISCUSSION AND CONCLUSIONS: This study documented a high prevalence of severe PD among PWUD during the COVID-19 pandemic compared with pre-COVID-19 data. Social determinants such as food insecurity and mobility issues, alongside demographic and substance use-related factors, were linked to distress. Evidence-based risk mitigation strategies for this population could reduce negative consequences in future pandemics or disruptions.

Gender, sexual orientation identity, and initiation of amphetamine injecting among people who inject drugs: Examination of an expanding drug era in Montreal, Canada, 2011-19.

BACKGROUND: Amphetamine injection is expanding in North America and has been associated with male homosexuality among people who inject drugs (PWID). Applying subcultural evolution theory, we examined overall and gender-stratified trends in amphetamine injection and assessed sexual orientation as a gender-specific predictor of initiation among PWID in Montreal, Canada. METHODS: Data were from HEPCO, an open prospective cohort of PWID. Gender and sexual orientation were self-identified at enrolment. Interviewer-administered questionnaires at three-monthly (HCV RNA-negative participants) or yearly (RNA-positive) intervals captured past three-month amphetamine injection and covariates. Annual prevalence and linear trends in amphetamine injection were estimated using GEE. Incidence was computed among naïve individuals and hazard ratios for initiation estimated using gender-stratified, time-varying Cox regression models. RESULTS: 803 participants contributed 8096 observations between March 2011 and December 2019. Annual prevalence of amphetamine injecting increased from 3.25% [95%CI: 2.06-4.43%] to 12.7% [9.50-16.0] (trend p<0.001). Bivariate Cox regression models suggested similar and divergent predictors of initiation by gender. Incidence was 3.27 per 100 person-years [95%CI: 2.51-4.18] among heterosexual men, 7.18 [3.50-13.2] among gay/bisexual men, 1.93 [0.78-4.02] among heterosexual women and 5.30 [1.69-12.8] among gay/bisexual women. Among men, gay/bisexual identity doubled risk of initiation after adjusting for age, ethnicity, calendar year (aHR 2.16 [1.07-4.36]) and additional covariates (2.56 [1.24-5.30]). Among women, evidence for an association with gay/bisexual identity was inconclusive (aHR 2.63 [0.62-11.2]) and sample size precluded further adjustment CONCLUSIONS: Prevalence of amphetamine injection among PWID increased four-fold from 2011 to 2019, with elevated risk of initiation in gay and bisexual men.

"Apparently, you can only be treated once": A qualitative study exploring perceptions of hepatitis C and access to treatment among people who inject drugs visiting a needle and syringe program.

BACKGROUND: Access to hepatitis C care within harm reduction community organizations for people who inject drugs is crucial for achieving hepatitis C elimination. However, there is a lack of data on how perceptions of hepatitis C and treatment have changed among individuals visiting these organizations during the era of direct-acting antivirals (DAAs). This study aimed to explore the perceptions of hepatitis C and treatment access for (re)infection among individuals visiting a needle and syringe program in Canada. METHODS: Eighteen semi-structured interviews were conducted with individuals who recently injected drugs and visited a needle and syringe program. The interviews were guided by the Common-Sense Self-Regulation Model (CS-SRM) and aimed to explore cognitive and emotional representations of hepatitis C, perceptions of treatment, coping strategies and sources of information. Interviews were audio recorded, transcribed, and coded using thematic analysis. RESULTS: Most of the participants identified as male, were of white ethnicity and had a median age of 45. While most underscored the therapeutic advancements and the effectiveness of DAAs, they expressed confusion regarding the mechanisms of access to treatment, especially in cases of reinfection. Perceptions of the controllability of hepatitis C were significantly influenced by the stigmatizing discourse surrounding treatment access, cost, and public coverage. This influence extended to their intentions for seeking treatment. Participants emphasized the social consequences of hepatitis C, including stigma. Emotional representations of hepatitis C evolved along the care cascade, encompassing initial shock at diagnosis and later fear of reinfection following successful treatment. CONCLUSION: Nearly a decade after the advent of DAAs, misinformation about treatment access persists. Findings underscore a nexus of internalized and institutionalized stigma associated with hepatitis C, drug use, and the challenges of cost and access to treatment, pointing to a clear need for education and service delivery optimisation in harm reduction community organizations.

Co-Constructing a Community-Based Telemedicine Program for People With Opioid Use Disorder During the COVID-19 Pandemic: Lessons Learned and Implications for Future Service Delivery.

The COVID-19 pandemic triggered unprecedented expansion of telemedicine, including in the delivery of opioid agonist treatment (OAT) for people with opioid use disorder (OUD). However, many people with OUD lack the technological resources necessary for remote care, have complex needs, and are underserved, with precarious access to mainstream services. To address the needs of these individuals, we devised a unique program to deliver OAT via telemedicine with the support of community outreach workers in Montreal (Quebec, Canada). The program was co-constructed by the service de médecine des toxicomanies of the Centre hospitalier de l'Université de Montréal (CHUM-SMT)-a hospital-based addiction medicine service-and CACTUS Montréal-a community-based harm reduction organization known and trusted by its clientele. All procedures were jointly developed to enable flexible and rapid appointment scheduling. CACTUS Montréal workers promoted the program, facilitated private on-site telemedicine connections to the CHUM-SMT, accompanied patients during web-based appointments if requested, and provided ongoing holistic support and follow-up. The CHUM-SMT offered individualized OAT regimens and other health services as needed. Overall, our experience as clinicians and community-based workers intimately involved in establishing and running this initiative suggests that participants found it to be convenient, nonjudgmental, and responsive to their needs, and that the implication of CACTUS Montréal was highly valued and integral to patient engagement and retention. Beyond the context of the COVID-19 pandemic, similar programs may present a flexible and accessible means to deliver alternative treatment options for people with OUD disengaged from traditional care, bridge gaps between communities and health providers, and improve access to care in rural or remote settings.

HCV treatment initiation in the era of universal direct acting antiviral coverage - Improvements in access and persistent barriers.

BACKGROUND: Barriers to HCV treatment initiation persisted after the introduction of direct-acting antivirals (DAAs) in Canada among people who inject drugs (PWID); whether DAA universal coverage lifted these barriers remain unknown. We assessed the evolution of HCV treatment initiation and associated factors among PWID in Montreal, Canada, comparing eras of IFN-based regimens (2011-2013), of DAA restricted access (2014-02/2018), and universal coverage (03/2018-03/2020). METHODS: We included chronically HCV-infected participants followed in a community-based PWID cohort in Montreal, Canada between 2011 and 03/2020 and collected data at 3-month intervals. Time-updated Cox regressions were conducted to examine 9 variables of interest associated with treatment initiation overall and for each of the three eras. RESULTS: Of 276 participants, 126 initiated treatment during follow-up. Yearly initiation increased from 3% in 2011 to 19% in 2016, and 54% in 2018. PWID aged >40 (vs. ≤40) were twice as likely to initiate treatment in 2014-02/2018 (HR: 2.02 95%CI: [1.24-3.28]) but not in other periods (2011-2013: 0.55 [0.25-1.22]; 03/2018-03/2020: 1.14 [0.59-2.22])). Odds of initiation were lower for men than women in all periods, with women three times more likely to be treated under universal coverage (0.30 [0.11-0.77] vs 2011-2013: 0.67 [0.25-1.78] and 2014-02/2018: 0.75 [0.42-1.35]). Recent incarceration was negatively associated with initiation throughout all periods (2011-2013: 0.57 [0.13-2.43]; 2014-03/2018: 0.39 [0.17-0.91]; 03/2018-03/2020: 0.25 [0.07-0.83]). Barriers associated with high injection frequency appear to have diminished since DAA introduction (2014-02/2018: 0.71 [0.42-1.20]; 03/2018-03/2020: 1.05 [0.52-2.11] vs. 2011-2013: 0.26 [0.08-0.88]). Contact with a primary care physician and engagement in opioid agonist therapy were positively associated with treatment initiation, though estimates were attenuated under universal coverage relative to previous eras. CONCLUSION: Treatment initiation rates have increased since the introduction of universal DAA coverage, though barriers such as incarceration persist.

Self-reported impacts of the COVID-19 pandemic among people who use drugs: a rapid assessment study in Montreal, Canada.

BACKGROUND: People who use drugs (PWUD) are at high risk of experiencing indirect harms of measures implemented to curb the spread of COVID-19, given high reliance on services and social networks. This study aimed to document short-term changes in behaviours and health-related indicators among PWUD in Montreal, Canada following declaration of a provincial health emergency in Quebec. METHODS: We administered a structured rapid assessment questionnaire to members of an existing cohort of PWUD and individuals reporting past-year illicit drug use recruited via community services. Telephone and in-person interviews were conducted in May-June and September-December 2020. Participants were asked to report on events and changes since the start of the health emergency (March 13, 2020). Descriptive analyses were performed. RESULTS: A total of 227 participants were included (77% male, median age = 46, 81% Caucasian). 83% and 41% reported past six-month illicit drug use and injection drug use, respectively. 70% of unstably housed participants reported increased difficulty finding shelter since the start of the health emergency. 48% of opioid agonist treatment recipients had discussed strategies to avoid treatment disruptions with providers; 22% had missed at least one dose. Many participants perceived increased difficulty accessing non-addiction health care services. Adverse changes were also noted in indicators pertaining to income, drug markets, drug use frequency, and exposure to violence; however, many participants reported no changes in these areas. Among persons reporting past six-month injection drug use, 79% tried to access needle-syringe programmes during the health emergency; 93% of those obtained services. 45% tried to access supervised injection sites, of whom 71% gained entry. CONCLUSIONS: This snapshot suggests mixed impacts of the COVID-19 pandemic on PWUD in Montreal in the months following declaration of a provincial health emergency. There were signals of increased exposure to high-risk environments as well as deteriorations in access to health services. Pandemic-related measures may have lasting impacts among vulnerable subgroups; continued monitoring is warranted.

Ageing and older people who use illicit opioids, cocaine or methamphetamine: a scoping review and literature map.

AIMS: To provide an overview of research literature on ageing and older people who use illicit opioids and stimulants by documenting the conceptual frameworks used and content areas that have been investigated. METHODS: We conducted a scoping review of literature relating to ageing and older people who use illicit stimulants and opioids, defining 'older' as 40 years and above. Primary studies, secondary studies and editorials were included. Searches were conducted in PubMed and Embase in July 2020 and March 2021; the Cochrane library was searched in November 2021. Charted data included methodological details, any conceptual frameworks explicitly applied by authors and the content areas that were the focus of the publication. We developed a hierarchy of content areas and mapped this to provide a visual guide to the research area. RESULTS: Of the 164 publications included in this review, only 16 explicitly applied a conceptual framework. Seven core content areas were identified, with most publications contributing to multiple content areas: acknowledgement of drug use among older people (n = 64), health status (n = 129), health services (n = 109), drug use practices and patterns (n = 84), social environments (n = 74), the criminal legal system (n = 28) and quality of life (n = 15). CONCLUSIONS: The literature regarding older people who use illicit drugs remains under-theorized. Conceptual frameworks are rarely applied and few have been purposely adapted to this population. Health status and health services access and use are among the most frequently researched topics in this area.

Injecting frequency trajectories and hepatitis C virus acquisition: Findings from a cohort of people who inject drugs in Montréal, Canada.

BACKGROUND: Frequent injecting increases hepatitis C (HCV) acquisition risk among people who inject drugs (PWID). However, few studies have examined how temporal fluctuations in injecting frequency may effect HCV infection risk. Thus, this study examined HCV incidence according to injecting frequency trajectories followed by PWID over one year in Montréal, Canada. METHODS: At three-month intervals from March 2011 to June 2016, HCV-uninfected PWID (never infected or cleared infection) enrolled in the Hepatitis Cohort (HEPCO) completed interviewer-administered questionnaires and HCV testing. At each visit, participants reported the number of injecting days (0-30 days) for each of the past three months. In previous work, using group-based trajectory modeling, we identified five injecting frequency trajectories followed by participants over one year (months 1-12 of follow-up), including sporadic, infrequent, increasing, decreasing, and frequent injecting. In this study, we estimated group-specific HCV incidence (months 1-63 of follow-up) using posterior probabilities to assign participants to their most likely trajectory group. RESULTS: Of 386 participants (mean age=40, 82% male, 48% never HCV-infected), 72 acquired HCV during 893 person-years of follow-up. HCV incidence for the whole study sample was 8.1 per 100 person-years (95%CI=6.4-10.1). Trajectory group-specific HCV incidences were highest for those injecting drugs with decreasing (23.9, 14.4-37.5) or increasing frequency (16.0, 10.1-24.3), intermediate for those injecting at consistently high frequency (10.2, 5.4-17.8), and lowest for those injecting infrequently (3.9, 2.2-6.5) or sporadically (4.3, 2.2-7.6). CONCLUSION: Results suggest that PWID at highest HCV risk are those injecting at high frequency, either transitorily (increasing, decreasing injecting) or consistently (frequent injecting). This study highlights changes in injecting frequency as a potentially important dimension to consider among the factors leading to HCV acquisition. Clinical and public health interventions tailored to PWID with different injecting frequency profiles may contribute to HCV prevention.

Gender-specific associations between psychological distress and injecting risk behaviours among people who inject drugs in Montreal, Canada.

BACKGROUND: Psychological distress is common among people who inject drugs (PWID) and may be associated with HCV-related risk behaviours. Previous studies have documented increased vulnerability to both psychological distress and HCV infection among female relative to male PWID. It is, however, unclear whether behavioural responses to distress differ by gender. This study estimated gender-specific associations between psychological distress and i) binge drug injection, and ii) sharing of injection materials. METHODS: Data were drawn from HEPCO, a longitudinal cohort study involving three-monthly interviews with active PWID in Montreal, Canada. Past-month psychological distress was assessed with the Kessler (K10) scale, categorized for descriptive analyses as minimal (score 10-15), moderate (16-21), high (22-29), or severe (30-50). Binge was defined as injecting large quantities of drugs until participants could no longer continue (past 3 months). Sharing was defined as injection with previously-used needles or equipment (past 3 months). Generalized additive models were fit to estimate smooth, nonlinear associations between K10 scores and risk behaviours, by gender. Models were adjusted for known determinants of drug-related harms and included random intercepts to model within-subject correlation. RESULTS: 805 individuals (82% male) provided 8158 observations (2011-2020). High to severe levels of distress were common and more frequent among women (55% vs 37%). Among men, the odds of binge and sharing monotonically and non-linearly increased with increasing scores of psychological distress. Associations for binge among women were attenuated relative to men but nevertheless increased with distress, albeit in a linear fashion. Sharing was not associated with distress among women. CONCLUSION: Psychological distress was differentially associated with injecting risk behaviours among men and women who inject drugs. Assessment of distress may provide novel prevention opportunities for select PWID. Further investigation into gender differences is warranted to inform development and tailoring of interventions.

Socioeconomic stability is associated with lower injection frequency among people with distinct trajectories of injection drug use.

BACKGROUND: Little is known about how socioeconomic circumstances relate to injection frequencies among people who inject drugs (PWID) with diverse trajectories of injection. We aimed to characterize trajectories of injection drug use in a community-based sample of PWID over 7.5 years and to investigate the extent to which two modifiable factors reflecting socioeconomic stability-stable housing and stable income-relate to injection frequencies across distinct trajectories. METHODS: HEPCO is an open, prospective cohort study of PWID living in Montréal with repeated follow-up at three-month or one-year intervals. Self-reported data on injection frequency, housing and income are collected at each visit. Injection frequency was defined as the number of injection days (0-30), reported for each of the past three months. Using group-based trajectory modeling, we first estimated average trajectories of injection frequency. Then, we estimated the trajectory group-specific average shift upward or downward associated with periods of stable housing and stable income relative to periods when these conditions were unstable. RESULTS: Based on 19,527 injection frequency observations accrued by 529 participants followed over 2011-2019 (18.3% female, median age: 41), we identified five trajectories of injection frequency: three characterized by sustained injection at different frequencies (28% infrequent; 19% fluctuating; 19% frequent), one by a gradual decline (12%), and another by cessation (28%). Periods of stable housing and stable income were each independently associated with a lower injection frequency, on average, in all five trajectory groups (2.2-7.5 fewer injection days/month, depending on the factor and trajectory group). CONCLUSION: Trajectories of injection drug use frequency were diverse and long-lasting for many PWID. Despite this diversity, socioeconomic stability was consistently associated with a lower injection frequency, emphasizing the close relationship between access to fundamental necessities and injection patterns in all PWID, irrespective of whether they are on a path to cessation or sustained injecting.

Relative 'greenness' and not availability of public open space buffers stressful life events and longitudinal trajectories of psychological distress.

Despite evidence of associations between urban green space exposure and mental health, explanatory mechanisms and the role of green space qualities remain unclear. This prospective cohort study (n = 929) examined the distinct relationships of residential public open space (POS) availability and 'greenness' with four-year trajectories of psychological distress in Montreal, Canada. Stress-buffering and main effect mechanisms were tested under the respective hypotheses that POS exposures 1) attenuate the impact of stressful events on psychological distress and 2) protect against psychological distress independently of exposure to stressful events. Results from growth mixture models indicate that residing among 'greener' POS protects against rising distress through both mechanisms. Conversely, POS availability was not associated with trajectories of distress when holding greenness constant. Findings reinforce the need to consider the quality as well as quantity of public open space in urban environments.

A rapid review of the impacts of "Big Events " on risks, harms, and service delivery among people who use drugs: Implications for responding to COVID-19.

BACKGROUND: "Big Events" are major disruptions to physical, political, and economic environments that can influence vulnerability to drug-related harms. We reviewed the impacts of Big Events with relevance to the COVID-19 pandemic on drug-related risk and harms and access to drug treatment and harm reduction services. METHODS: We conducted a rapid review of quantitative, qualitative, and mixed methods literature relating to the following Big Events: respiratory infection pandemics, natural disasters, financial crises, and heroin shortages. Included studies reported data on changes to risks, harms, and/or service provisioning for people who use illicit drugs (other than cannabis) in the context of these Big Events. Searches were conducted in PubMed in May 2020, and two reviewers screened studies for inclusion. Peer-reviewed studies published in English or French were included. We used a narrative synthesis approach and mapped risk pathways identified in the literature. RESULTS: No studies reporting on respiratory infection pandemics were identified. Twelve studies reporting on natural disaster outcomes noted marked disruption to drug markets, increased violence and risk of drug-related harm, and significant barriers to service provision caused by infrastructure damage. Five studies of the 2008 global financial crisis indicated increases in the frequency of drug use and associated harms as incomes and service funding declined. Finally, 17 studies of heroin shortages noted increases in heroin price and adulteration, potentiating drug substitutions and risk behaviors, as well as growing demand for drug treatment. CONCLUSION: Current evidence reveals numerous risk pathways and service impacts emanating from Big Events. Risk pathway maps derived from this literature provide groundwork for future research and policy analyses, including in the context of the COVID-19 pandemic. In light of the findings, we recommend responding to the pandemic with legislative and financial support for the flexible delivery of harm reduction services, opioid agonist treatment, and mental health care.

Deconstructing the 'cheque effect': short-term changes in injection drug use after receiving income assistance and associated factors.

BACKGROUND AND AIMS: Disbursement of income assistance has been temporally associated with intensified drug use and related harms (coined the 'cheque effect'). However, relationships to injection drug use (IDU) remain understudied. We examined short-term 'cheque effects' and associated factors among people who inject drugs (PWID). DESIGN: Cross-sectional analysis nested within a cohort study. SETTING: Montreal, Quebec, Canada. PARTICIPANTS: PWID receiving income assistance, with no employment income. A total of 613 PWID (median age 41, 83% male) contributed 3269 observations from 2011 to 2017. MEASUREMENTS AND METHODS: At each cohort visit, an interviewer-administered questionnaire captured retrospective reports of injection-related behaviour during the 2-day periods (i) before and (ii) including/after receiving last month's income assistance payment (number of injections; drugs injected; any receptive syringe-sharing). The relative likelihood (odds) and magnitude (rate) of an increase in injection frequency ('cheque effect') were estimated in relation to social and behavioural factors using logistic and negative binomial regression in a covariate-adjusted two-part model. FINDINGS: Prevalence of IDU and syringe-sharing were, respectively, 1.80 and 2.50 times higher in the days following versus preceding cheque receipt (P < 0.001). Among people with past-month IDU, most observations showed increased injection frequency (52%) or no change in injection frequency (44%). The likelihood of a 'cheque effect' was positively associated with cocaine injection [versus injection of other substances, odds ratio (OR) = 2.639, 95% confidence interval (CI) = 2.04-3.41], unstable housing (OR = 1.272, 95% CI = 1.03-1.57) and receiving opioid agonist therapy (OR =1.597, 95% CI = 1.27-2.00) during the same month. Magnitude of the 'cheque effect' was positively associated with cocaine injection [rate ratio (RR) = 1.795, 95% CI = 1.43-2.16], unstable housing (RR = 1.198, 95% CI = 1.02-1.38) and frequent injection (RR = 2.938, 95% CI = 2.43-3.44), but inversely associated with opioid agonist therapy (RR = 0.817, 95% CI = 0.68-0.95) and prescription opioid injection (RR = 0.794, 95% CI = 0.66-0.93). CONCLUSION: Among people who inject drugs in Montreal, Canada, injection drug use and receptive syringe-sharing appear to be more prevalent in the 2 days after versus before receiving income assistance. The odds and rate of individual-level increases in injection frequency appear to be positively associated with cocaine injection (versus injection of other substances) and unstable housing.

Real-World Eligibility for HIV Pre-exposure Prophylaxis Among People Who Inject Drugs.

Recent studies have highlighted the efficacy of and willingness to use pre-exposure prophylaxis (PrEP) to prevent HIV infection among people who inject drugs (PWID), however knowledge of real-world applicability is limited. We aimed to quantify the real-world eligibility for HIV-PrEP among HIV-negative PWID in Montreal, Canada (n = 718). Eligibility was calculated according to US Centers for Disease Control and Prevention (CDC) guidelines and compared to risk of HIV acquisition according to the assessing the risk of contracting HIV (ARCH-IDU) risk screening tool. Over one-third of participants (37%) were eligible for HIV PrEP, with 1/3 of these eligible due to sexual risk alone. Half of participants were considered high risk of HIV acquisition according to ARCH-IDU, but there was poor agreement between the two measures. Although a large proportion of PWID were eligible for HIV-PrEP, better tools that are context- and location-informed are needed to identify PWID at higher risk of HIV acquisition.

Prevalence of Injecting Drug Use and Coverage of Interventions to Prevent HIV and Hepatitis C Virus Infection Among People Who Inject Drugs in Canada.

Objectives. To determine the number of people who inject drugs (PWID) in Canada and the annual coverage of opioid agonist treatment (OAT) and needle-and-syringe provision for PWID.Methods. We estimated the number of PWID in 11 of 13 Canadian provinces and territories in 2011 by using indirect multiplier methods based on provincial and territorial methadone recipient totals and proportion of surveyed PWID receiving methadone. We modeled annual increases for 2011 to 2016 on Quebec and British Columbia longitudinal data. We calculated needle-and-syringe coverage (World Health Organization [WHO] recommendation: ≥ 200 per PWID) and OAT coverage (WHO recommendation: ≥ 40 per 100 PWID) per province and territory annually.Results. An estimated 130 000 individuals in Canada (0.55%) injected drugs in 2011, increasing to 171 900 individuals (0.70%) in 2016. Needle-and-syringe coverage increased from 193 to 291 per PWID, and OAT coverage increased from 55 to 66 per 100 PWID over the study period.Conclusions. While the number of PWID increased between 2011 and 2016, OAT coverage remained high, and needle-and-syringe coverage generally improved over time.Public Health Implications. These data will inform public health surveillance, service planning, and resource allocation, and assist monitoring of treatment and harm-reduction coverage outcomes.

Sexual behaviour as a risk factor for hepatitis C virus infection among people who inject drugs in Montreal, Canada.

Hepatitis C virus (HCV) acquisition remains high in key risk environments including injection drug use and sex between men. However, few studies examine the independent contribution of sexual behaviour to HCV acquisition among people who inject drugs (PWID). We estimated HCV incidence and examined sexual behaviour as a time-varying predictor of HCV acquisition in a prospective cohort study of PWID in Montreal (2004-2017). Initially, HCV-negative participants completed behavioural questionnaires and HCV antibody testing (6 months until 2011, 3 months thereafter). A time-updating exposure variable (no sex, opposite-sex partner only, ≥1 same-sex partner) was generated for the previous 6/3 months. Time to HCV seroconversion was examined using Cox regression analysis, adjusted for age, unstable housing and incarceration (both past 3 months), and daily, heroin, cocaine and prescription opioid injecting (all past month). Among 440 PWID (baseline: median age 33 years, 18.9% female, 1.4% HIV-positive), 156 participants seroconverted during follow-up (overall incidence rate: 11.9/100 person-years [PY]). Incidence was lowest in the no sex group (8.70 and 2.91 cases/100 PY in males and females, respectively) and highest in the ≥1 same-sex partner group (24.14 and 21.97 cases/100 PY in males and females, respectively). Among males, HCV risk was 47% lower in those reporting no sex compared to ≥1 same-sex partner (adjusted hazard ratio: 0.53, 95% confidence interval: 0.28, 0.99). In this cohort of PWID, reporting recent same-sex partners was associated with greater risk of HCV acquisition among males, necessitating targeted harm reduction strategies that consider the complex interplay of sexual and injecting risk behaviours.

Opioid agonist treatment dosage and patient-perceived dosage adequacy, and risk of hepatitis C infection among people who inject drugs.

BACKGROUND: Opioid agonist treatment is considered important in preventing acquisition of hepatitis C virus (HCV) among people who inject drugs; however, the role of dosage in opioid agonist treatment is unclear. We investigated the joint association of prescribed dosage of opioid agonist treatment and patient-perceived dosage adequacy with risk of HCV infection among people who inject drugs. METHODS: We followed prospectively people who inject drugs at risk of acquiring HCV infection (who were RNA negative and HCV-antibody negative or positive) in Montréal, Canada (2004-2017). At 6-month, then 3-month intervals, participants were tested for HCV antibodies or RNA, and completed an interviewer-administered behavioural questionnaire, reporting the following: current exposure to opioid agonist treatment (yes/no), prescribed dosage either high (methadone ≥ 60 mg/d or buprenorphine ≥ 16 mg/d) or low, and perceived dosage adequacy (adequate/inadequate). We then assigned participants to 1 of 5 exposure categories: no opioid agonist treatment, high dosage of opioid agonist treatment perceived to be adequate, high dosage perceived to be inadequate, low dosage perceived to be adequate or low dosage perceived to be inadequate. To estimate associations between categories of opioid agonist treatment dosage and incident HCV infection, we conducted Cox regression analyses, adjusting for multiple confounding factors. RESULTS: Of 513 participants (median age 35.0 yr, 77.6% male), 168 acquired HCV over 1422.6 person-years of follow-up (incidence 11.8/100 person-years, 95% confidence interval [CI] 10.1-13.7). We observed a gradient in the relative risks of HCV infection across categories of opioid agonist treatment dosage. Compared with people who inject drugs not receiving opioid agonist treatment, adjusted hazard ratios were 0.43 (95% CI 0.23-0.84) for those receiving high dosages perceived to be adequate, 0.61 (95% CI 0.25-1.50) for those receiving high dosages perceived to be inadequate, 1.22 (95% CI 0.74-2.00) for those receiving low dosages perceived to be adequate and 1.94 (95% CI 1.11-3.39) for those receiving low dosages perceived to be inadequate. INTERPRETATION: Risk of HCV infection varies considerably according to dosage of opioid agonist treatment and patient-perceived adequacy, with associations indicating both protective and harmful effects relative to no exposure to opioid agonist treatment.