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

Evaluating the effects of supervised consumption sites on housing prices in Montreal, Canada using interrupted time series and hedonic price models

Background

In 2017, three brick and mortar supervised consumption sites (SCS) opened in Montreal, Canada. Opponents argued the sites would attract people who use drugs and reduce local real estate prices.

Methods

We used interrupted time series and hedonic price models to evaluate the effects of Montreal's SCS on local real estate prices. We linked the Quebec Professional Association of Real Estate Brokers' housing sales data provided by Centris Inc. with census tract data and gentrification scores. Homes sold within 200 m of the SCS locations between 1 January 2014 and 31 December 2021 were included. We adjusted for internal (e.g., number of bed/bathrooms, unit size) and external attributes (e.g., neighbourhood demographics), and included a spatio-temporal lag to account for correlation between sales. For sensitivity analysis we used site-specific dummy variables to better account for unmeasured neighbourhood differences, and repeated analyses using 500 m and 1000 m radii.

Results

We observed a price shock after the opening of the first two SCS in June 2017 (level effect: -10.5%, 95% CI: -19.1%, -1.1%) but prices rose faster month-to-month (trend effect: 1.1%, 95% CI: 0.7%, 1.6%) after implementation. Following the implementation of the third site in November 2017 there was no immediate impact (level effect: 2.4%, 95% CI: -10.4%, 17.0%) but once more prices roses faster (0.9%, 95% CI: 0.4%, 1.5%) thereafter. When we replaced neighbourhood attributes with a site-specific dummy variable, we observed the same pattern. Sales' prices dropped (level effect: -9.6%, 95% CI: -15.0%, -3.8%) but rose faster month-to-month (trend effect: 0.9%, 95% CI: 0.6%, 1.2%) following June 2017's SCS implementations, with no level effect (4.9%, 95% CI: -7.3%, 18.6%) and a positive trend (0.9%, 95% CI: 0.5%, 1.3%) after November 2017's SCS opening. In most 500 m and 1000 m radii models, there were no immediate shocks following SCS opening, however, positive trend effects persisted in all models.

Conclusion

Our models suggest homes sold near SCS may experience a price shock immediately post-implementation, with evidence of market recovery in the months that follow.

Ongoing Gaps in the Hepatitis C Care Cascade during the Direct-Acting Antiviral Era in a Large Retrospective Cohort in Canada: A Population-Based Study

To achieve hepatitis C virus (HCV) elimination, high uptake along the care cascade steps for all will be necessary. We mapped engagement with the care cascade overall and among priority groups in the post-direct-acting antivirals (DAAs) period and assessed if this changed relative to pre-DAAs. We created a population-based cohort of all reported HCV diagnoses in Quebec (1990-2018) and constructed the care cascade [antibody diagnosed, RNA tested, RNA positive, genotyped, treated, sustained virologic response (SVR)] in 2013 and 2018. Characteristics associated with RNA testing and treatment initiation were investigated using marginal logistic models via generalized estimating equations. Of the 31,439 individuals HCV-diagnosed in Quebec since 1990 and alive as of 2018, there was significant progress in engagement with the care cascade post- vs. pre-DAAs; 86% vs. 77% were RNA-tested, and 64% vs. 40% initiated treatment. As of 2018, a higher risk of not being RNA-tested or treated was observed among individuals born <1945 vs. >1965 [hazard ratio (HR); 95% CI; 1.35 (1.16-1.57)], those with material and social deprivation [1.21 (1.06-1.38)], and those with alcohol use disorder [1.21 (1.08-1.360]. Overall, non-immigrants had lower rates of RNA testing [0.76 (0.67-0.85)] and treatment initiation [0.63 (0.57-0.70)] than immigrants. As of 2018, PWID had a lower risk of not being RNA tested [0.67 (0.61-0.85)] but a similar risk of not being treated, compared to non-PWID. Engagement in the HCV care cascade have improved in the post-DAA era, but inequities remain. Vulnerable subgroups, including certain older immigrants, were less likely to have received RNA testing or treatment as of 2018 and would benefit from focused interventions to strengthen these steps.

Prevalence of xylazine among people who inject drugs seeking medical care at a syringe services program clinic: Miami, Florida, 2023

Background

We aimed to report the preliminary xylazine prevalence among people who inject drugs (PWID) treated at a student-run free clinic in Miami, FL, USA and to identify characteristics associated with screening positive for xylazine.

Methods

A retrospective chart review of 59 patients presenting to a syringe services program (SSP) clinic in was conducted between April 27th and August 17th, 2023. We measured presence of xylazine with rapid visual immunoassay strips on patient urine samples.

Results

Xylazine was present in 55.9 % (33/59) of urine samples including 2 without detected opioids. Xylazine presence was significantly associated with unsheltered homelessness (p = 0.018), presence of wound(s) (p = 0.008), and testing positive for hepatitis C antibody (p = 0.014), fentanyl (p = 0.005) and MDMA (p = 0.002).

Conclusions

A high prevalence of xylazine in the Southeastern United States furthers evidence of the geographical spread of xylazine and rapidly evolving illicit drug supply. Widespread xylazine screening is urgently needed to inform people who inject drugs and to studyinterventions to minimize harms associated with xylazine.

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.

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.

Understanding syringeability and injectability of high molecular weight PEO solution through time-dependent force-distance profiles

Opioid medications play a vital role in treating moderate to severe pain. Unfortunately, many drug misusers and abusers attempt to alter the formulations or properties of these drugs by manipulation, (e.g., crushing, chewing, smoking, snorting, injecting). The intravenous (IV) route is most dangerous to abusers, as the drugs directly enter the circulatory system and produce intense euphoria. To obtain a full understanding of the impact of syringe factors (e.g., needle gauge size, needle length, syringe barrel size), on the ease of injection, we undertook a comprehensive assessment of syringeability and injectability of manipulated abuse-deterrent formulations (ADFs). A texture analyzer-based testing method was developed for the measurement of the resistance force of pulling, holding, and pushing phases of injections. Results showed that the finer needle gauge sizes required higher injection force to withdraw drug solutions. In addition, the syringed liquid volume was highly dependent on needle gauge size, holding time, and sample viscosity. In most cases, a lower needle gauge number and a longer holding time increased the syringed volume. Needle length was highly correlated to injection force (R² = 0.99). Using longer needles to inject drug solution requires greater force. Furthermore, large barrel size was correlated to pushing force (R² = 0.99); thus, increasing the difficulty of pushing the plunger of a large syringe with one hand. Finally, relationships between injection force, sample viscosity, and testing conditions were elucidated using a mathematical model, which could be used in the future to assess and predict injection force of solution samples.

Hepatitis C virus risk among young people who inject drugs

Background

Injection drug use (IDU) is the leading risk factor for hepatitis C virus (HCV) transmission in the U.S. While the general risk factors for HCV transmission are known, there is limited work on how these factors interact and impact young people who inject drugs (YPWID).

Methods

Project data were drawn from a study of 539 New York City (NYC) residents ages 18-29 who were recruited via Respondent-Driven Sampling and, reported past-month non-medical use of prescription opioids and/or heroin. Analyses are based on a subsample of 337 (62%) who reported injecting any drug in the past 12 months. All variables were assessed via self-report, except HCV status, which was established via rapid antibody testing. Integrating the observed statistical associations with extant literature on HCV risk, we also developed a qualitative system dynamics (SD) model to use as a supplemental data visualization tool to explore plausible pathways and interactions among key risk and protective factors for HCV.

Results

Results showed a 31% HCV antibody prevalence with an overall incidence of 10 per 100 person-years. HCV status was independently correlated with having shared cookers with two or more people (AOR = 2.17); injected drugs 4–6 years (AOR = 2.49) and 7 or more years (AOR = 4.95); lifetime homelessness (AOR = 2.52); and having been incarcerated two or more times (AOR = 1.99). These outcomes along with the extant literature on HCV risk were used to develop the qualitative SD model, which describes a causal hypothesis around non-linearities and feedback loop structures underlying the spread of HCV among YPWID.

Conclusions

Despite ongoing harm reduction efforts, close to a third of YPWID in the community sample have been exposed to HCV, have risks for injection drug use, and face challenges with structural factors that may be preventing adequate intervention. The qualitative SD model explores these issues and contributes to a better understanding of how these various risk factors interact and what policies could potentially be effective in reducing HCV infections.

Polysubstance use and re-incarceration in the 12-months after release from jail: a latent transition analysis of rural Appalachian women

Background: Rural areas have high rates of opioid and stimulant involved polysubstance use which are known to contribute to overdose. Justice-involved women are likely to have multiple substance use disorders and are particularly vulnerable in rural areas where treatment is limited.Objectives: The research had three aims to (1) identify the patterns of polysubstance use of rural Appalachian justice-involved women, (2) examine how women's engagement in polysubstance use changed in the 12-months following initial release from jail, and (3) determine if women's changes in substance use patterns were associated with re-incarceration during the 12-months of post-release follow-up.Methods: A total of 339 women with recent substance use histories were randomly recruited from three rural jails. Latent transition analysis of women's substance use from baseline (in jail) to 6 and 12-months was examined, including the effect of re-incarceration on transitions (changes in substance use patterns).Results: Three latent classes were found: High Polysubstance/injection drug use (IDU) (36.3% baseline), Opioid/Benzo (Benzodiazepine) Involved Polysubstance Use (57.3% baseline), and Low Use (6.4% baseline). Polysubstance use classes were characterized by use of opioids and benzodiazepines; the High Polysubstance/IDU class was distinct in co-use and injection use of methamphetamine. Post-release, women transitioned to latent classes of reduced substance use and/or reduced injection drug use, particularly in the first six months. Women who were re-incarcerated during follow-up were likely to remain engaged in, or transition to, the High Polysubstance/IDU class (ORs: 3.14-46.56).Conclusion: Justice-involved women in Appalachia reported risky polysubstance use. The first six-months post-release were a critical period for changes in substance use.

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.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06085-3.

Health harms of non-medical prescription opioid use: A systematic review

ISSUES

Non-medical prescription opioid use (NMPOU) contributes substantially to the global burden of morbidity. However, no systematic assessment of the scientific literature on the associations between NMPOU and health outcomes has yet been undertaken.

APPROACH

We undertook a systematic review evaluating health outcomes related to NMPOU based on ICD-10 clinical domains. We searched 13 electronic databases for original research articles until 1 July 2021. We employed an adaptation of the Oxford Centre for Evidence-Based Medicine 'Levels of Evidence' scale to assess study quality.

KEY FINDINGS

Overall, 182 studies were included. The evidence base was largest on the association between NMPOU and mental and behavioural disorders; 71% (129) studies reported on these outcomes. Less evidence exists on the association of NMPOU with infectious disease outcomes (26; 14%), and on external causes of morbidity and mortality, with 13 (7%) studies assessing its association with intentional self-harm and 1 study assessing its association with assault (<1%).

IMPLICATIONS

A large body of evidence has identified associations between NMPOU and opioid use disorder as well as on fatal and non-fatal overdose. We found equivocal evidence on the association between NMPOU and the acquisition of HIV, hepatitis C and other infectious diseases. We identified weak evidence regarding the potential association between NMPOU and intentional self-harm, suicidal ideation and assault.

DISCUSSION AND CONCLUSIONS

Findings may inform the prevention of harms associated with NMPOU, although higher-quality research is needed to characterise the association between NMPOU and the full spectrum of physical and mental health disorders.

Gaps in hepatitis C virus prevention and care for HIV-hepatitis C virus co-infected people who inject drugs in Canada

BACKGROUND

People who inject drugs (PWID) living with HIV are a priority population for eliminating hepatitis C virus (HCV) as a public health threat. Maximizing access to HCV prevention and treatment strategies are key steps towards elimination. We aimed to evaluate engagement in harm reduction programs and HCV treatment, and to describe injection practices among HIV-HCV co-infected PWID in Canada from 2003 to 2019.

METHODS

We included Canadian Coinfection Cohort study participants who reported injecting drugs between 2003 and 2019 in Quebec, Ontario, Saskatchewan, and British Columbia, Canada. We investigated temporal trends in HCV treatment uptake, efficacy, and effectiveness; injection practices; and engagement in harm reduction programs in three time periods based on HCV treatment availability: 1) interferon/ribavirin (2003-2010); 2) first-generation direct acting antivirals (DAAs) (2011-2013); 3) second-generation DAAs (2014-2019). Harm reduction services assessed included needle and syringe programs (NSP), opioid agonist therapy (OAT), and supervised injection sites (SIS).

RESULTS

Median age of participants (N = 1,077) at cohort entry was 44 years; 69% were males. Province-specific HCV treatment rates increased among HCV RNA-positive PWID, reaching 16 to 31 per 100 person-years in 2014-2019. Treatment efficacy improved from a 50 to 70% range in 2003-2010 to >90% across provinces in 2014-2019. Drug injecting patterns among active PWID varied by province, with an overall decrease in cocaine injection frequency and increasing opioid injections. In the most recent time period (2014-2019), needle/syringe sharing was reported at 8-22% of visits. Gaps remained in engagement in harm reduction programs: NSP use decreased (58-70% of visits), OAT engagement among opioid users was low (8-26% of visits), and participants rarely used SIS (1-15% of visits).

CONCLUSION

HCV treatment uptake and outcomes have improved among HIV-HCV coinfected PWID. Yet, this population remains exposed to drug-related harms, highlighting the need to tie HCV elimination strategies with enhanced harm reduction programs to improve overall health for this population.

Telehealth for people who inject drugs: An acceptable method of treatment but challenging to access

BACKGROUND

While telemedicine is seen as an emerging practice that will outlast the COVID-19 pandemic, it can reduce health services for those with limited internet and technological devices access or sufficient literacy.

OBJECTIVE(S)

The aim of this study was to explore the feasibility of using telehealth with people who inject drugs (PWID).

METHODS

A survey on availability and accessibility of different methods of communication was administered to a sample of PWID from an ongoing longitudinal cohort in Montréal, Canada.

RESULTS

Among the 96 respondents, phone calls were generally considered acceptable (89.6%) although availability was low (50%). Acceptability and availability of social media were 26% and 41.7%, respectively. Internet-based communication applications were considered acceptable to use for telehealth in 28.1% of participants, even if not frequently available (8.3%).

CONCLUSIONS

Telehealth is an acceptable form of treatment for PWID, but may be challenging due to low availability of phone or internet access.

Evaluating Montréal's harm reduction interventions for people who inject drugs: protocol for observational study and cost-effectiveness analysis

INTRODUCTION

The main harm reduction interventions for people who inject drugs (PWID) are supervised injection facilities, needle and syringe programmes and opioid agonist treatment. Current evidence supporting their implementation and operation underestimates their usefulness by excluding skin, soft tissue and vascular infections (SSTVIs) and anoxic/toxicity-related brain injury from cost-effectiveness analyses (CEA). Our goal is to conduct a comprehensive CEA of harm reduction interventions in a setting with a large, dispersed, heterogeneous population of PWID, and include prevention of SSTVIs and anoxic/toxicity-related brain injury as measures of benefit in addition to HIV, hepatitis C and overdose morbidity and mortalities averted.

METHODS AND ANALYSIS

This protocol describes how we will develop an open, retrospective cohort of adult PWID living in Québec between 1 January 2009 and 31 December 2020 using administrative health record data. By complementing this data with non-linkable paramedic dispatch records, regional monthly needle and syringe dispensation counts and repeated cross-sectional biobehavioural surveys, we will estimate the hazards of occurrence and the impact of Montréal's harm reduction interventions on the incidence of drug-use-related injuries, infections and deaths. We will synthesise results from our empirical analyses with published evidence to simulate infections and injuries in a hypothetical population of PWID in Montréal under different intervention scenarios including current levels of use and scale-up, and assess the cost-effectiveness of each intervention from the public healthcare payer's perspective.

ETHICS AND DISSEMINATION

This study was approved by McGill University's Institutional Review Board (Study Number: A08-E53-19B). We will work with community partners to disseminate results to the public and scientific community via scientific conferences, a publicly accessible report, op-ed articles and open access peer-reviewed journals.

Found Down Extremity Compartment Syndrome Secondary to Substance Use: An Observational Multicenter Study

With the worsening opioid epidemic in America, more patients are developing found down extremity compartment syndrome (FDECS). The purpose of this study was to describe this patient population, including their presenting symptoms, laboratory test results, and clinical outcomes.

Methods

We performed a 2-center retrospective review of adult patients who developed FDECS secondary to substance use from January 2006 to December 2019. Patients were managed operatively or nonoperatively at the surgeon's discretion. Data on patient demographic characteristics, laboratory values, hospital course, and clinical outcomes were collected from electronic medical records.

Results

In this study, 91 patients were included: 85 patients were managed operatively, and 6 patients were managed nonoperatively. Most patients were male, and the mean patient age (and standard deviation) was 37 ± 11 years. Opioids were the most common substance used. Patients managed operatively underwent a mean of 4 ± 3 surgical procedures, 44% received a skin graft, 25% developed a wound infection, and 11% underwent limb amputation. Patients managed nonoperatively did not undergo a subsequent fasciotomy or amputation. At a mean follow-up of 2.3 years, persistent weakness (66%), pain (78%), persistent sensory deficits (53%), and contractures (18%) were common.

Conclusions

Patients who develop FDECS secondary to substance use have high surgical complication rates and poor clinical outcomes. We found high rates of wound infection, revision surgical procedures, and amputation, often leaving young adults with lifelong disability.

Level of Evidence

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Diversity of incarceration patterns among people who inject drugs and the association with incident hepatitis C virus infection

BACKGROUND

Little is known about the relationship between short-term incarceration and risk of hepatitis C virus (HCV) infection among people who inject drugs (PWID). We investigated whether varying patterns of recent incarceration lasting less than two years are associated with HCV acquisition risk in this population.

METHODS

We followed prospectively PWID at risk of acquiring HCV infection in Montréal (2004-2019). At 6-month (up until 2011), then 3-month intervals, participants were tested for HCV antibodies or RNA, and self-reported whether they have been incarcerated in each of the previous 6 or 3 months. If incarcerated, they reported the setting and time spent in incarceration. We fit three separate multivariable time-updated Cox regression models, one for each measure of incarceration: any incarceration lasting less than two years (yes/no), incarceration stratified by setting (local police station/provincial prison/no) and incarceration stratified by time in incarceration (≤1 week/>1 week and ≤1 month/>1 month and <2 years/no).

RESULTS

Among 709 PWID followed over 2315.2 person-years, HCV incidence was 9.9/100 person-years (95% confidence interval (CI): 8.7-11.2)]. During follow-up, 248 PWID (35.0%) reported at least one recent incarceration episode of less than two years. Overall, compared to PWID who did not experience incarceration in the prior 6 or 3 months, PWID who did were 1.56 (95% CI: 1.13, 2.17) times more likely to acquire HCV. We found no statistically significant difference in the magnitude of associations across categories of setting and time in incarceration (likelihood ratio test P= 0.53 and 0.44, respectively).

CONCLUSION

Any recent incarceration lasting less than two years, regardless of the setting and time in incarceration, was associated with an elevated risk of HCV acquisition among PWID. Findings support the need to expand access to harm-reduction programs in short-term incarceration settings and, in parallel, to prioritise public health-oriented alternatives to incarcerating PWID where possible.

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.

Prevalence and correlates of multiple non-fatal opioid overdoses among people who inject drugs who utilise needle syringe programs in Australia

BACKGROUND

Non-fatal overdose (NFOD) is a major cause of morbidity among people who inject drugs (PWID) and multiple NFOD is associated with increased risk of fatal overdose. Despite this, few studies have examined the prevalence and correlates of drug-specific multiple NFOD. The current study aimed to determine the prevalence and correlates of recent multiple non-fatal opioid overdose (NFOOD) among PWID who access needle syringe programs (NSPs) in Australia.

METHODS

The Australian Needle and Syringe Program Survey is conducted annually and was conducted at 46 sites across Australia in 2019. Participation involves completion of a self-administered questionnaire and a capillary dried blood spot for HIV and hepatitis C virus testing. In 2019, respondents who reported a minimum of one NFOOD in the previous 12 months (recent NFOOD) were asked to complete supplementary questions regarding their last NFOOD. Bivariate and multivariate logistic regression were used to determine factors independently associated with multiple recent NFOOD.

RESULTS

A total of 222 respondents reported recent NFOOD. Respondents were predominantly male (59%), one third (39%) were aged less than 39 years and 73% reported last injecting heroin at their last NFOOD. One in two respondents (48%, n = 107) reported multiple opioid overdoses (median 3, interquartile range 2-5). The odds of reporting multiple NFOOD were higher among respondents who reported injecting in a public location at their last NFOOD (adjusted odds ratio [AOR] 2.10, 95% CI 1.14-3.90, p = 0.018) and benzodiazepine use in the 12 h prior to NFOOD (AOR 2.74, 95% CI 1.50-4.99, p = 0.001).

CONCLUSIONS

Multiple NFOOD was prevalent among PWID who utilised NSPs who reported recent NFOOD. Public injecting and benzodiazepine use were associated with increased risk of multiple NFOOD, and there is a need for interventions specifically targeting PWID who report these high risk injecting practices.

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.

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.

Prevalence, Characteristics, and Management of Chronic Noncancer Pain Among People Who Use Drugs: A Cross-Sectional Study

INTRODUCTION

Most studies on chronic noncancer pain (CNCP) in people who use drugs (PWUD) are restricted to people attending substance use disorder treatment programs. This study assessed the prevalence of CNCP in a community-based sample of PWUD, identified factors associated with pain, and documented strategies used for pain relief.

METHODS

This was a cross-sectional study nested in an ongoing cohort of PWUD in Montreal, Canada. Questionnaires were administered to PWUD seen between February 2017 and January 2018. CNCP was defined as pain lasting three or more months and not associated with cancer.

RESULTS

A total of 417 PWUD were included (mean age = 44.6 ± 10.6 years, 84% men). The prevalence of CNCP was 44.8%, and the median pain duration (interquartile range) was 12 (5-18) years. The presence of CNCP was associated with older age (>45 years old; odds ratio [OR] = 1.8, 95% CI = 1.2-2.7), male sex (OR = 2.3, 95% CI = 1.2-4.2), poor health condition (OR = 1.9, 95% CI = 1.3-3.0), moderate to severe psychological distress (OR = 2.9, 95% CI = 1.8-4.7), and less frequent cocaine use (OR = 0.5, 95% CI = 0.3-0.9). Among CNCP participants, 20.3% used pain medication from other people, whereas 22.5% used alcohol, cannabis, or illicit drugs to relieve pain. Among those who asked for pain medication (N = 24), 29.2% faced a refusal from the doctor.

CONCLUSIONS

CNCP was common among PWUD, and a good proportion of them used substances other than prescribed pain medication to relieve pain. Close collaboration of pain and addiction specialists as well as better pain assessment and access to nonpharmacological treatments could improve pain management in PWUD.

Characterization of HCV-infected people who inject drugs (PWID) in the setting of clinical care in Canada (CAPICA): A retrospective study

BACKGROUND: People who use drugs (PWUD) are among the highest risk category for becoming infected with the hepatitis C virus (HCV) in Canada. There is a need for more information on the demographics of HCV-infected PWUD/PWID who have recently injected drugs or who are actively injecting drugs. METHODS: CAPICA was a multicentre, retrospective database/chart review conducted from October 2015 to February 2016 that was designed to characterize HCV-infected people who inject drugs (PWID) and are enrolled in clinical care in Canada. The aim was to identify factors of health care engagement essential in the design systems of HCV care and treatment in this population. The study enrolled 420 patients with a history of injection drug use within the last 12 months who had been diagnosed with chronic viremic HCV infection and had been participants in an outpatient clinical care setting in the past 12 months. Patients who were co-infected with HIV/HCV were excluded. RESULTS: Harm reduction programs were in place at 92% (11/12) of the sites, and 75% (9) of these sites offered opioid agonist therapy (OAT), with 48% of the patients currently taking OAT. HCV genotype 1a was most prevalent (56%), followed by G3 (34%), and the most common fibrosis score was F1 (34%). The average reinfection rate was about 5%. Seventeen percent of the patients were undergoing HCV treatment or had recently failed therapy, while 83% were not being treated. CONCLUSIONS: In a multivariate analysis, the following factors were significantly associated with treatment: increasing age (OR 1.10), a fibrosis score of F4 (OR 4.91), moderate alcohol consumption (OR 3.70), and not using a needle exchange program (OR 6.95).

The role of prison-based interventions for hepatitis C virus (HCV) micro-elimination among people who inject drugs in Montréal, Canada

BACKGROUND

In Canada, hepatitis C virus (HCV) transmission primarily occurs among people who inject drugs (PWID) and people with experience in the prison system bare a disproportionate disease burden. These overlapping groups of individuals have been identified as priority populations for HCV micro-elimination in Canada, which is currently not on track to achieve its elimination targets. Considering the missed opportunities to intervene in provincial prisons, this study aims to estimate the population-level impact of prison-based interventions and post-release risk reduction strategies on HCV transmission among PWID in Montréal, a Canadian city with high HCV burden.

METHODS

A dynamic HCV transmission model among PWID was developed and calibrated to community and prison bio-behavioural surveys in Montréal. Then, the relative impact of prison-based testing and treatment or post-release linkage to care (both 90% testing and 75% treatment coverage), alone or in combination with strategies that reduce the heightened post-release transmission risk by 50%, was estimated from 2018 to 2030, and compared to counterfactual scenarios.

RESULTS

Prison-based test-and-treat strategies could lead to the greatest declines in incidence (48%; 95%CrI: 38-57%) over 2018-2030 and prevent the most new first chronic infections (22%; 95%CrI: 16-28%) among people never exposed to HCV. Prison testing and post-release linkage to care lead to a slightly lower decrease in incidence and prevented fraction of new chronic infections. Combining test-and-treat with risk reduction measures could further its epidemiological impact, preventing 35% (95%CrI: 29-40%) of new first chronic infections. When implemented concomitantly with community-based treatment scale-up, prison-based interventions had synergistic effects, averting a higher fraction of new first chronic infections.

CONCLUSION

Offering HCV testing and treatment in provincial prisons, where incarcerations are frequent and sentences short, could change the course of the HCV epidemic in Montréal. Prison-based interventions with potential integration of post-release risk reduction measures should be considered as an integral part of HCV micro-elimination strategies in this setting.

Prescription opioid injection among young people who inject drugs in New York City: a mixed-methods description and associations with hepatitis C virus infection and overdose

Aim

Evidence is emerging that prescription opioid (PO) injection is associated with increased health risks. This mixed-methods study compares the mechanics of PO and heroin injection and examines the demographic and drug-related correlates of lifetime PO injection in a sample of young people who inject drugs (PWID) in New York City (NYC).

Methods

Qualitative analysis of 46 semi-structured interviews with young adult opioid users ages 18–32. Interview segments describing PO injection were analyzed for common themes. Quantitative analysis of structured interviews with 539 young adult opioid users ages 18–29 recruited via respondent-driven sampling (RDS). Analyses are based on the subsample of 353 participants (65%) who reported having ever injected drugs. All variables were assessed via self-report, except hepatitis C virus status, which was established via rapid antibody testing.

Results

Participants described injecting POs and reported that preparing abuse-deterrent pills for injection is especially cumbersome, requiring extended manipulation and large amounts of water. Injecting POs, in contrast to injecting heroin, requires repeated injections per injection episode. Among RDS-recruited participants, the majority of injectors reported injecting POs, sporadically (33%) or regularly (26%), but often infrequently (≤ 7 days/month). In separate multivariable analyses controlling for syringe- and cooker-sharing, ever injecting POs was a significant predictor of testing HCV antibody-positive (AOR = 2.97) and lifetime experience of non-fatal overdose (AOR = 2.51). Ever injecting POs was independently associated with lifetime homelessness (AOR = 2.93) and having grown up in a middle-income ($51,000–100,000/year vs. ≤ $50,000/year; AOR = 1.86) or a high-income household (> $100,000/year vs. ≤ $50,000/year; AOR = 2.54).

Conclusions

Even in an urban environment like NYC with widespread heroin access, most young PWID have injected POs, although less frequently than heroin. PO injection involves practices that are known to increase risk for blood-borne viral infection (e.g., repeated injections) and predicted testing HCV-positive, as well as overdose. PO injection may also serve as a marker for a subgroup of PWID at elevated risk for multiple drug use-related comorbidities. Programs that provide prevention services to PWID need to tailor harm reduction measures and messaging to the specific practices and harms associated with the injection of POs.

Hepatitis C Coinfection and Mortality in People Living with HIV in Middle Tennessee

HIV and hepatitis C virus (HCV) coinfection is associated with poor health outcomes. This study was designed to assess risk factors for and mortality with coinfection before direct-acting antiviral treatment availability in a state with an evolving opioid epidemic. HCV infection was determined from review of the medical record at two clinics serving the majority of people living with HIV (PLWH) in care in Middle Tennessee from 2004 to 2013. Association of potential risk factors with HCV-positivity was assessed using logistic regression. Association of HCV-positivity with mortality was assessed with a Cox proportional hazards model, adjusting for selected covariates. A total of 3,501 patients were included: 24% female; 51% men who have sex with men; 47% white; 44% African American/black; median age of 38 at their first visit; median most recent CD4 count 502 cells/μL (301-716); and HIV viral load 47 copies/mL (39-605); followed for a median of 3.0 (1-5) years. Prevalence of HCV was 13%. Those with a history of injection drug use (IDU) demonstrated the highest odds of HCV-positivity [odds ratio 12.94; 95% confidence interval (CI) 9.39-17.83]. There were 305 deaths; median age at death was 47 years (40-53). HCV coinfection was associated with greater mortality (hazard ratio 1.61; 95% CI 1.20-2.17; p < .001). Among PLWH, HCV coinfection was associated with IDU and an independent predictor of mortality. These results affirm the importance of HCV coinfection and inform interventions targeting the continuum of HCV care, uptake of HCV treatment, and the impact of drug use in this population.

The opioid mortality epidemic in North America: do we understand the supply side dynamics of this unprecedented crisis?

While there has been extensive attention to the 'demand side' - or use and adverse consequences, including mortality - of the 'opioid crisis' presently unfolding across North America, few considerations have focused on the supply side. This paper examines the supply side dynamics of this unprecedented public health phenomenon. We provide evidence for several interrelated supply-side elements that have contributed to the present public health crisis. We observe that initially, persistently high levels of prescription opioid availability and use exposed large proportions of the North American population to opioids, resulting in correspondingly high levels of medical and non-medical use (e.g., involving diversion). While various intervention measures to control prescription opioid availability and use have been implemented in recent years, leading to eventual reductions in opioid dispensing levels, these occurred late in the crisis's evolution. Moreover, these supply reductions have not been met by corresponding reductions in opioid use or demand levels. These growing discrepancies between opioid demand and prescription-based sources have left major gaps in opioid supplies. In response to such supply gaps, highly potent and toxic illicit opioid products have rapidly proliferated across North America, and become a core driver of the dramatic spikes in opioid overdose fatality levels in recent years. These supply-related interrelations are corroborated by a corresponding increase in illicit opioid-related fatalities, which arose just as medical opioid supplies began to decrease in many jurisdictions. Improved analyses and understanding of the supply-side dynamics of the opioid crisis are urgently needed in order to inform future intervention and policy development. Meanwhile, the high mortality toll related to illicit, highly toxic opioid exposure requires sustained solutions, including supply-oriented measures (e.g., safer opioid distribution for at-risk users) towards improved public health protection.

Racial/Ethnic and Gender Differences in Associations of Medication-Assisted Therapy and Reduced Opioid Use between Outpatient Treatment Admission and Discharge

Medication-assisted therapy (MAT) for opioid use disorders is an effective treatment strategy. Racial/ethnic and gender disparities in MAT utilization have been documented, but less is known about disparities in MAT outcomes. We used the Treatment Episodes Dataset-Discharges (TEDS-D; 2015- 2017) to identify outpatient treatment episodes with heroin or illicit opioids indicated at admission (n = 232,547). We used multivariate logistic regression to model the association between MAT and a reduction in opioid use between treatment admission and discharge. We explored moderation by race/ethnicity and gender by including an interaction term. We identified a strong moderating effect of race/ethnicity and gender. American Indian/Alaska Native (AI/AN) women demonstrated the strongest association between MAT (versus no MAT) and a reduction in opioid use (aOR = 6.05, 95% CI = 4.81- 7.61), while White men demonstrated the weakest association (aOR = 2.78, CI = 2.70- 2.87). Our findings could inform changes in clinical MAT settings that are based on harm reduction and the incremental transition from illicit opioids to medication-assistance among a diverse opioid use disorder population.

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.

Associations between housing stability and injecting frequency fluctuations: findings from a cohort of people who inject drugs in Montréal, Canada

BACKGROUND

The relationship between housing stability and drug injecting is complex, as both outcomes fluctuate over time. The objectives were to identify short-term trajectories of housing stability and injecting frequency among people who inject drugs (PWID) and examine how patterns of injecting frequency relate to those of housing stability.

METHODS

At three-month intervals, PWID enrolled between 2011 and 2016 in the Hepatitis Cohort completed an interviewer-administered questionnaire and were tested for hepatitis C and HIV infections. At each visit, participants reported, for each of the past three months, the accommodation they lived in the longest (stable/unstable) and the number of injecting days (0-30). Group-based dual trajectory modeling was conducted to identify housing stability and injecting frequency trajectories evolving concomitantly over 12 months and estimate the probabilities of following injecting trajectories conditional upon housing trajectories.

RESULTS

386 participants were included (mean age 40.0, 82 % male). Three housing stability trajectories were identified: sustained (53 %), declining (20 %), and improving (27 %). Five injecting frequency trajectories were identified: sporadic (26 %), infrequent (34 %), increasing (15 %), decreasing (11 %), and frequent (13 %). PWID with improving housing were less likely to increase injecting (8 %) compared to those with sustained (17 %) or declining housing (17 %).

CONCLUSIONS

Improving housing was associated with a lower probability of increasing injecting compared to declining housing, while sustained housing stability was associated with a higher probability of increasing injecting compared to improving housing. Therefore, policies to improve PWID's access to stable housing are warranted and may reduce, to some extent, drug injecting and related harms.

Changes in Reported Injection Behaviors Following the Public Health Response to an HIV Outbreak Among People Who Inject Drugs: Indiana, 2016

A syringe services program (SSP) was established following the Indiana HIV outbreak among persons who inject drugs (PWID) in Scott County. Among Indiana-based PWID, we examined injection behaviors associated with HIV status, SSP use after its establishment, and changes in injection behaviors after the outbreak response. During 2016, we interviewed 200 PWID and assessed injection behaviors before the response by HIV status. We reported injection behaviors prior to the response and used Fisher's exact Chi square tests (P < 0.05) to assess differences by HIV status. Next, among persons who injected both before (July-December 2014) and after (past 30 days) the response, we (1) reported the proportion of persons who used the SSP to obtain sterile syringes, and assessed differences in SSP use by HIV status using Fisher's exact Chi square tests; and (2) compared distributive and receptive sharing of injection equipment and disposal of syringes before and after the outbreak response, and assessed statistical differences using McNemar's test. We also compared injection behaviors before and after the response by HIV status. Injecting extended release oxymorphone (Opana® ER); receptive sharing of syringes and cookers; and distributive sharing of cookers, filters, or water before the response were associated with HIV infection. SSP use was high (86%), particularly among HIV-positive compared with HIV-negative persons (98% vs. 84%). Injection equipment sharing decreased and safe disposal of used syringes increased after the response, especially among HIV-positive persons. Injection equipment sharing contributed to the outbreak. High SSP use following the response, particularly among HIV-positive persons, contributed to decreased high-risk injection practices.

Longitudinal migration patterns from an open illicit drug scene among people who use illicit drugs in Vancouver, Canada

The objective of this study was to identify migration patterns from an open illicit drug scene (the Downtown Eastside [DTES] neighborhood) and describe factors associated with these migration patterns. Data were derived from three cohorts of people who use illicit drugs in Vancouver, Canada. Defined using latent class growth analysis, we identified four distinct migration trajectory groups: 1) consistently living in the DTES (47.8%); 2) early migration out, with a median time of migrating out of DTES of 5.3 months (21.5%); 3) late migration out, with a median time of migrating out of DTES of 38.0 months (20.1%); and 4) frequent revisit back-and-forth to DTES (10.6%). In a multivariable model, compared to the "consistently living in the DTES" group, factors associated with the "frequent revisit" group included being enrolled in non-pharmacological addiction treatment and having an HCV-positive serostatus. Factors associated with the "early migration out" group included being enrolled in detoxification or in other non-pharmacological addiction treatment, later calendar year, being on income assistance, living in a single room occupancy hotel, and having an HCV-positive serostatus. These findings point to the need for appropriate distribution of services in order to meet the needs of this population.

Associations between perceived illicit fentanyl use and infectious disease risks among people who inject drugs

BACKGROUND

Over the last several years, fentanyl has been introduced into the illicit drug supply in the United States. While the impact of fentanyl on overdose fatalities is clear, the increase in fentanyl use may also be affecting drug use practices with implications for infectious disease transmission. We conducted a cross-sectional survey to explore associations of perceived illicit fentanyl use with opioid use frequency, injection frequency and syringe sharing among people who inject drugs in two California cities.

METHODS

People who inject drugs (PWID) were recruited from community settings in Los Angeles and San Francisco, CA from June 2017 to September 2018. Multivariable logistic regression was used to explore adjusted associations between perceived illicit fentanyl use and high frequency opioid use, high frequency injection and syringe sharing.

RESULTS

Among the 395 study participants, the median age of participants was 44 years; 74% of participants were cisgender male; 73% reported to be homeless; 61% lived in San Francisco and 39% in Los Angeles. The prevalence of perceived illicit fentanyl use in the past six months was 50.4% (95% confidence interval (CI): 45.4%-55.3%) among PWID. Findings from our adjusted logistic regression models suggested that people reporting perceived illicit fentanyl use had a greater odds of high frequency opioid use (adjusted odds ratio (aOR) = 2.36; 95% CI: 1.43-3.91; p = 0.001), high frequency injection (aOR = 1.84; 95% CI: 1.08-3.13; p = 0.03) and receptive syringe sharing (aOR = 2.16; 95% CI: 1.06-4.36; p = 0.03), as compared to people using heroin and other street drugs but not fentanyl.

CONCLUSION

People reporting perceived illicit fentanyl use were at increased risk for injection-related infectious disease risks. Actions must be taken to reduce these risks, including improved access to syringe service programs and opioid treatment and consideration of innovative approaches, such as supervised consumption services.

Specificity of personality relationships to particular forms of concurrent substance use among methadone maintenance therapy clients

OBJECTIVE

A mainstay treatment for opioid addiction in North America is methadone maintenance therapy (MMT) - a form of opiate agonist therapy (OAT). While efficacious for treating opioid addiction, MMT fails to address the concurrent polysubstance use that is common among opioid dependent clients. Moreover, psychosocial approaches for addressing polysubstance use during MMT are lacking. Our study's goals were to validate the use of the four-factor personality model of substance use vulnerability in MMT clients, and to demonstrate theoretically-relevant relationships of personality to concurrent substance use while receiving MMT.

METHOD

Respondents included 138 daily-witnessed MMT clients (65.9% male, 79.7% Caucasian), mean age (SD) 40.18 (11.56), recruited across four Canadian MMT clinics. Bayesian confirmatory factor analysis was used to establish the structural validity of the four-factor personality model of substance use vulnerability (operationalized with the Substance Use Risk Profile Scale [SURPS]) in MMT clients. SURPS personality scores were then used as predictors for specific forms of recent (past 30-day) substance use.

RESULTS

Using a latent hierarchal model, hopelessness was associated with recent opioid use; anxiety sensitivity with recent tranquilizer use; and sensation seeking with recent alcohol, cannabis, and stimulant use.

CONCLUSION

Personality is associated with substance use patterns and may be an appropriate target for intervention for those undergoing MMT to reduce opioid use, and potentially dangerous concurrent use of other drugs, while receiving methadone.

Opioid-Related Diagnoses and Concurrent Claims for HIV, HBV, or HCV among Medicare Beneficiaries, United States, 2015

Unsterile opioid injection increases risk for infection transmission, including HIV, hepatitis B virus (HBV), or hepatitis C virus (HCV). We assess prevalence of and risk factors associated with opioid overdose and infections with HIV, HBV, or HCV among Medicare beneficiaries with opioid-related fee-for-service claims during 2015. We conducted a cross-sectional analysis to estimate claims for opioid use and overdose and HIV, HBV, or HCV infections, using data from US Medicare fee-for-service claims. Beneficiaries with opioid-related claims had increased odds for HIV (2.3; 95% confidence interval (CI), 2.3–2.4), acute HBV (6.7; 95% CI, 6.3–7.1), chronic HBV (5.0; 95% CI, 4.7–5.4), acute HCV (9.6; 95% CI, 9.2–10.0), and chronic HCV (8.9; 95% CI, 8.7–9.1). Beneficiaries with opioid-related claims and for HIV, HBV, or HCV infection, respectively, had a 1.1–1.9-fold odds for having a claim for opioid overdose. Independent risk factors for opioid overdose and each selected infection outcome included age, sex, race/ethnicity, region, and residence in a high-vulnerability county. Having opioid-related claims and selected demographic attributes were independent, significant risk factors for having HIV, HBV, or HCV claims among US Medicare beneficiaries. These results might help guide interventions intended to reduce incidences of HIV, HCV, and HBV infections among beneficiaries with opioid-related claims.

Association between mental health service utilisation and sharing of injection material among people who inject drugs in Montreal, Canada

BACKGROUND

High-risk injection behaviors are associated with high prevalence of mental health problems among people who inject drugs (PWID). However, whether the use of mental health services is associated with lower risk of sharing injection material remains undetermined. This study aims to examine the association between mental health service utilisation and receptive sharing risk, and determine the potential modifying effect of psychological distress on this association.

METHODS

Participants answered an interviewer-administered questionnaire at 3-month intervals gathering information on sociodemographic characteristics, substance use and related behaviors, services utilisation and significant mental health markers. Relationship between the use of mental health services and receptive sharing was modeled using the generalized estimating equation (GEE), controlling for age at baseline, gender, and other potential confounders. Psychological distress was estimated using the Kessler Psychological Distress Scale (K10). Effect modification was investigated by adding an interaction term in the univariate GEE analysis.

RESULTS

358 participants contributed to 2537 visits (median age 40.3, 82% male). Mental health service utilisation was reported in 631 visits (25%), receptive sharing in 321 visits (13%) and severe psychological distress in 359 visits (14%). In multivariate GEE analyses, a significant association was identified between receptive sharing and the use of mental health services (aOR = 0.69; 95% CI = 0.50-0.94). We found no evidence of effect modification by psychological distress.

CONCLUSION

Among PWID, mental health service utilisation was associated with lower likelihood of receptive sharing, regardless of level of psychological distress. These findings should be taken into account when designing harm reduction strategies for this population.

Opioid epidemic and liver disease

Opioid use in the United States and in many parts of the world has reached epidemic proportions. This has led to excess mortality as well as significant changes in the epidemiology of liver disease. Herein, we review the impact of the opioid epidemic on liver disease, focusing on the multifaceted impact this epidemic has had on liver disease and liver transplantation. In particular, the opioid crisis has led to a significant shift in incident hepatitis C virus infection to younger populations and to women, leading to changes in screening recommendations. Less well characterized are the potential direct and indirect hepatotoxic effects of opioids, as well as the changes in the incidence of hepatitis B virus infection and alcohol abuse that are likely rising in this population as well. Finally, the opioid epidemic has led to a significant rise in the proportion of organ donors who died due to overdose. These donors have led to an overall increase in donor numbers, but also to new considerations about the better use of donors with perceived or actual risk of disease transmission, especially hepatitis C. Clearly, additional efforts are needed to combat the opioid epidemic. Moreover, better understanding of the epidemiology and underlying pathophysiology will help to identify and treat liver disease in this high-risk population.

A Randomized, Double-Blind, Double-Dummy, Placebo-Controlled, Intranasal Human Abuse Potential Study of Oxycodone ARIR, a Novel, Immediate-Release, Abuse-Deterrent Formulation

Objective

Prescription opioid abuse continues to be a public health concern. Oxycodone ARIR is an immediate-release (IR) oxycodone tablet composed of multiple overlapping barriers that deter manipulation of the tablet for non-oral abuse.

Design

This randomized, double-blind, double-dummy, active- and placebo-controlled, four-way crossover, intranasal human abuse potential study assessed the pharmacodynamics and pharmacokinetics of crushed intranasal oxycodone ARIR compared with crushed intranasal IR oxycodone and intact oral oxycodone ARIR.

Outcome Measures

Pharmacodynamic end points included mean maximum drug liking (E_max), as measured by subjects on a bipolar 100-mm visual analog scale (primary), and desire to take the drug again, overall drug liking, drug high, and good effects (secondary). Pharmacokinetic assessments included peak concentration and time to peak concentration.

Results

Twenty-nine subjects completed the treatment phase. Crushed intranasal oxycodone ARIR demonstrated a significant reduction of 46.9% and 23.4% in drug liking E_max compared with crushed intranasal IR oxycodone and intact oral oxycodone ARIR, respectively (P < 0.0001 for both). Significant reductions also were observed in desire to take the drug again, drug high, overall drug liking, and good effects when comparing crushed intranasal oxycodone ARIR with crushed intranasal IR oxycodone and intact oral oxycodone ARIR (P < 0.001 for all). Crushed intranasal oxycodone ARIR exhibited lower peak oxycodone plasma concentrations and slower time to peak concentration compared with crushed intranasal IR oxycodone and intact oral oxycodone ARIR. All treatments were well tolerated; adverse effects were typical of opioids or intranasal administration.

Conclusions

These data indicate that oxycodone ARIR has the potential to reduce abuse via the intranasal route.

Association of Injection Practices and Overdose With Drug Use Typologies: A Latent Class Analysis Among People Who Inject Drugs in Baltimore, 2017

Increasing overdose mortality and new HIV outbreaks in the U.S. highlight the need to identify risk behavior profiles among people who inject drugs (PWID). We characterized latent classes of drug use among a community-based sample of 671 PWID in Baltimore during 2017 and evaluated associations of these classes with sharing syringes, obtaining syringes from pharmacies or syringe services programs (SSPs), and nonfatal overdose in the past 6 months. We identified three classes of current drug use: infrequent use (76% of participants), prescription drug use (12%), and heroin and/or cocaine injection (12%). PWID in the heroin and/or cocaine injection and prescription drug use classes had higher odds of both overdose and sharing syringes (relative to infrequent use). PWID in the prescription drug use class were 64% less likely to obtain syringes through SSPs/pharmacies relative to heroin and/or cocaine injection. Harm reduction programs need to engage people who obtain prescription drugs illicitly.

Elimination of hepatitis C virus infection among people who use drugs: Ensuring equitable access to prevention, treatment, and care for all

There have been major strides towards the World Health Organization goal to eliminate hepatitis C virus (HCV) infection as a global public health threat. The availability of simple, well-tolerated direct-acting antiviral therapies for HCV infection that can achieve a cure in >95% of people has provided an important tool to help achieve the global elimination targets. Encouragingly, therapy is highly effective among people receiving opioid agonist therapy and people who have recently injected drugs. Moving forward, major challenges include ensuring that new infections are prevented from occurring and that people who are living with HCV are tested, linked to care, treated, receive appropriate follow-up, and have equitable access to care. This editorial highlights key themes and articles in a special issue focusing on the elimination of HCV among people who inject drugs. An overarching consideration flowing from this work is how to ensure equitable access to HCV treatment and care for all. This special issue maps the field in relation to: HCV prevention; the cascade of HCV care; strategies to enhance testing, linkage to care, and treatment uptake; and HCV treatment and reinfection. In addition, papers draw attention to the 'risk environments' and socio-ecological determinants of HCV acquisition, barriers to HCV care, the importance of messaging around the side-effects of new direct-acting antiviral therapies, the positive transformative potential of treatment and cure, and the key role of community-based drug user organizations in the HCV response. While this special issue highlights some successful efforts towards HCV elimination among people who inject drugs, it also highlights the relative lack of attention to settings in which resources enabling elimination are scarce, and where elimination hopes and potentials are less clear, such as in many low and middle income countries. Strengthening capacity in areas of the world where resources are more limited will be a critical step towards ensuring equity for all so that global HCV elimination among PWID can be achieved.

Transitioning from interferon-based to direct antiviral treatment options: A potential shift in barriers and facilitators of treatment initiation among people who use drugs?

BACKGROUND

Multiple barriers for accessing hepatitis C virus (HCV) treatment were identified during the interferon-based (IFN) treatment era for people who inject drugs (PWID). Whether these barriers persist since the introduction of IFN-free direct-acting antiviral (DAA) agents in Canada remains to be documented. This study examined temporal trends in HCV treatment initiation and associated factors during the transition from INF-based to all-oral DAA regimens.

METHODS

The study population was drawn from a prospective cohort of PWID in Montreal, Canada. At three-month/one-year intervals between 2011 and 2017, participants with chronic HCV infection completed an interviewer-administered questionnaire on socio-demographic characteristics, drug use and health service utilisation, including HCV treatment. Time-updated Cox multivariate regression models, stratified by DAA + INF (2011-2013) and all-oral DAA (2014-2017) availability periods, were conducted to examine associations between time to HCV treatment initiation and associated barriers and facilitators.

RESULTS

Of 308 participants (85% male, median age 42 [IQR: 33, 50]), 80 (26%) initiated HCV treatment during 915 person-years (PY). Incidence rates increased from 1.6 /100 PY (95%CI:0.9-2.6) in 2011 to 12.7 (10.6-15.1) in 2017 (p-trend = 0.0012). In multivariate analyses, visiting a primary care physician (2011-2013: aHR = 3.63[1.21-10.9]; 2014-2017: 2.52[1.10-5.77]) and frequent injection (0.23[0.05-0.99] and 0.49[0.24-0.99]) were consistently associated with treatment initiation. Participants aged >40 (2.27[1.24-4.13]), receiving opioid agonist therapy (OAT) (2.17[1.19-3.94]), and reporting prior HCV treatment (3.00[1.75-5.15]) were more likely to initiate treatment in the all-oral DAA period.

CONCLUSION

Treatment initiation increased between 2011 and 2017, but still remains low among PWID. Primary care visiting was a key facilitator regardless of the period, while engagement in OAT and health services, indicated by prior HCV treatment, increased the likelihood of treatment initiation in the DAA era. These findings suggest that access to health services is essential but not enough to scale up treatment in this population.

Effectiveness of medication assisted treatment for opioid use in prison and jail settings: A meta-analysis and systematic review

This study examined the state of the literature on the effectiveness of medication assisted treatment (MAT; methadone, buprenorphine, naltrexone) delivered in prisons and jails on community substance use treatment engagement, opioid use, recidivism, and health risk behaviors following release from incarceration. Randomized controlled trials (RCTs) and quasi-experimental studies published through December 2017 that examined induction to or maintenance on methadone (n = 18 studies), buprenorphine (n = 3 studies), or naltrexone (n = 3 studies) in correctional settings were identified from PsycINFO and PubMed databases. There were a sufficient number of methadone RCTs to meta-analyze; there were too few buprenorphine or naltrexone studies. All quasi-experimental studies were systematically reviewed. Data from RCTs involving 807 inmates (treatment n = 407, control n = 400) showed that methadone provided during incarceration increased community treatment engagement (n = 3 studies; OR = 8.69, 95% CI = 2.46; 30.75), reduced illicit opioid use (n = 4 studies; OR = 0.22, 95% CI = 0.15; 0.32) and injection drug use (n = 3 studies; OR = 0.26, 95% CI = 0.12; 0.56), but did not reduce recidivism (n = 4 studies; OR = 0.93, 95% CI = 0.51; 1.68). Data from observational studies of methadone showed consistent findings. Individual review of buprenorphine and naltrexone studies showed these medications were either superior to methadone or to placebo, or were as effective as methadone in reducing illicit opioid use post-release. Results provide the first meta-analytic summary of MATs delivered in correctional settings and support the use of MATs, especially with regard to community substance use treatment engagement and opioid use; additional work is needed to understand the reduction of recidivism and other health risk behaviors.

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.

Hepatitis C Virus Infection in Indigenous Populations in the United States and Canada

American Indian/Alaska Native (AI/AN) and Canadian Indigenous people are disproportionally affected by hepatitis C virus (HCV) infection yet are frequently underrepresented in epidemiologic studies and surveys often used to inform public health efforts. We performed a systematic review of published and unpublished literature and summarized our findings on HCV prevalence in these Indigenous populations. We found a disparity of epidemiologic literature of HCV prevalence among AI/AN in the United States and Indigenous people in Canada. The limited data available, which date from 1995, demonstrate a wide range of HCV prevalence in AI/AN (1.49%-67.60%) and Indigenous populations (2.28%-90.24%). The highest HCV prevalence in both countries was reported in studies that either included or specifically targeted people who inject drugs. Lower prevalence was reported in studies of general Indigenous populations, although in Canada, the lowest prevalence was up to 3-fold higher in Aboriginal people compared with general population estimates. The disparity of available data on HCV prevalence and need for consistent and enhanced HCV surveillance and reporting among Indigenous people are highlighted. HCV affects Indigenous peoples to a greater degree than the general population; thus we recommend tribal and community leaders be engaged in enhanced surveillance efforts and that funds benefitting all Indigenous persons be expanded to help prevent and cover health care expenses to help stop this epidemic.

An age-based analysis of nonmedical prescription opioid use among people who use illegal drugs in Vancouver, Canada

BACKGROUND

Nonmedical prescription opioid use (NMPOU) is a serious public health problem in North America. At a population-level, previous research has identified differences in the prevalence and correlates of NMPOU among younger versus older age groups; however, less is known about age-related differences in NMPOU among people who use illegal drugs.

METHODS

Data were collected between 2013 and 2015 from two linked prospective cohort studies in Vancouver, Canada: the At-Risk Youth Study (ARYS) and the Vancouver Injection Drug Users Study (VIDUS). Factors independently associated with NMPOU among younger (ARYS) and older (VIDUS) participants were examined separately using bivariate and multivariate generalized estimating equations.

RESULTS

A total of 1162 participants were included. Among 405 eligible younger participants (Median age = 25; Inter-Quartile Range [IQR]: 22-28), 40% (n = 160) reported engaging in NMPOU at baseline; among 757 older participants (Median age = 48, IQR: 40-55), 35% (n = 262) reported engaging in NMPOU at baseline. In separate multivariate analyses of younger and older participants, NMPOU was positively and independently associated with heroin use (younger: Adjusted Odds Ratio [AOR] = 3.12, 95% Confidence Interval [CI]: 2.08-4.68; older: AOR = 2.79, 95% CI: 2.08-3.74), drug dealing (younger: AOR = 2.22, 95% CI: 1.58-3.13; older: AOR = 1.87, 95% CI: 1.40-2.49), and difficulty accessing services (younger: AOR = 1.47, 95% CI: 1.04-2.09; older: AOR = 1.74, 95% CI: 1.32-2.29). Among the youth cohort only, NMPOU was associated with younger age (AOR = 1.12, 95% CI: 1.05-1.19), crack use (AOR = 1.56, 95% CI: 1.06-2.30), and binge drug use (AOR = 1.41, 95% CI: 1.00-1.97); older participants who engaged in NMPOU were more likely to report crystal methamphetamine use (AOR = 1.97, 95% CI: 1.46-2.66), non-fatal overdose (AOR = 1.76, 95% CI: 1.20-2.60) and sex work (AOR = 1.49, 95% CI: 1.00-2.22).

DISCUSSION

The prevalence of NMPOU is similar among younger and older people who use drugs, and independently associated with markers of vulnerability among both age groups. Adults who engage in NMPOU are at risk for non-fatal overdose, which highlights the need for youth and adult-specific strategies to address NMPOU that include better access to health and social services, as well as a range of addiction treatment options for opioid use. Findings also underscore the importance of improving pain treatment strategies tailored for PWUD.

Diffusion of medication drop-boxes in North Carolina from 2007 to 2016

INTRODUCTION

A permanent drug donation box ("drop-box") is one strategy implemented in communities across the United States to reduce the availability of excess controlled medications, including prescription opioids, for diversion. The objective of this study was to examine correlates of the diffusion and implementation of drop-boxes in North Carolina.

METHODS

We assessed the number and location of drop-boxes implemented in North Carolina. Cox proportional hazards models were used to examine covariates associated with drop-box implementation in NC counties (n = 100) between 2007 and 2016.

RESULTS

There were 311 drop-boxes implemented in 91 (out of 100) counties. Most drop-boxes were in law enforcement agencies (78.8%) and a growing number were in pharmacies (14.5%). Counties with a higher percentage of whites, more educated residents, a substance abuse prevention coalition, higher rates of controlled medications dispensed and prescription opioid overdose, and that were Appalachian were more likely to be early adopters. Rural counties were less likely to have a drop-box. In the multivariate model, only higher rate of controlled medicines dispensed was significant.

CONCLUSIONS

A growing number of drop-boxes are being implemented in law enforcement offices and pharmacies. Given that communities with higher rates of controlled medication dispensing likely have the highest need for disposal opportunities, it is promising that they are early adopters of drop-boxes. Future research should assess the effectiveness of drop-boxes as they become more widespread in a variety of locations.