"I'm just searching to get better": Constructions of treatment citizenship on injectable opioid agonist treatment

BACKGROUND

As part of the response to Canada's worsening overdose crisis driven by a toxic, adulterated drug supply, there has been increased attention to and expansion of drug treatment, options, including injectable opioid agonist treatment (iOAT). iOAT typically involves the, witnessed daily injection of opioids under healthcare provider supervision. There is a robust, evidence base on iOAT; however, there has been less focus on how people engage with this; treatment outside of clinical trials. This paper examines how people engage with iOAT programs, in expanded treatment settings in Canada, focusing on how the broader socio-structural context, shapes patient subjectivities in treatment.

METHODS

This study draws on critical ethnographic and community-based research approaches, conducted with people accessing four iOAT programs in Vancouver's Downtown Eastside; neighbourhood from May 2018 to November 2019. Data included in-depth baseline and followup, interviews and approximately 50 h of observation fieldwork conducted in one iOAT, program and with a subsample of participants in the surrounding neighbourhood. Analysis, leveraged the concepts of biological citizenship and structural vulnerability.

RESULTS

This analysis characterized three narrative frames-regular long-term engagers, pain, patients, and sporadic and short-term engagers-through in-depth case presentations of participants with distinct types of engagement with iOAT programs. Participants within these, narrative frames described a dominant form of iOAT citizenship, an autonomous patient who, regularly engages in treatment and avoids pleasure. However, structural vulnerabilities, including, homelessness and housing instability, entrenched poverty, criminal-legal system engagement, and unmanaged pain, shaped the ability of participants to make claims to this normative model of citizenship.

CONCLUSION

This study examined how structural vulnerabilities impact people's construction and ability to make iOAT citizenship claims. Findings point to the need for changes within and outside of iOAT programs, such as lower threshold treatment models, improved social services (e.g., secure housing), and pain management support.

Prevalence and Correlates of Heavy Alcohol use among People Living with HIV who use Unregulated Drugs in Vancouver, Canada

Among people living with HIV (PLWH), heavy alcohol use is associated with many negative health consequences. However, the impacts of heavy alcohol use are not well described for PLWH who use drugs. Thus, we investigated the prevalence and correlates of heavy alcohol use among a cohort of people who use drugs (PWUD) living with HIV in Vancouver, Canada. We accessed data from an ongoing community-recruited prospective cohort of PLWH who use drugs with linked comprehensive HIV clinical monitoring data. We used generalized linear mixed-effects modeling to identify factors longitudinally associated with periods of heavy alcohol use between December 2005 and December 2019. Of the 896 participants included, 291 (32.5%) reported at least one period with heavy alcohol use. Periods of recent incarceration (Adjusted Odds Ratio [AOR] = 1.48, 95% Confidence Interval [CI]: 1.01-2.17), encounters with police (AOR = 1.87, 95% CI: 1.37-2.56), and older age (AOR = 1.05, 95% CI: 1.02-1.07) were positively associated with heavy alcohol use. Engagement in drug or alcohol treatment (AOR = 0.54, 95% CI: 0.42-0.70) and male gender (AOR = 0.46; 95% CI: 0.27-0.78) were negatively associated with heavy alcohol use. We observed that heavy alcohol use was clearly linked to involvement with the criminal justice system. These findings, together with the protective effects of substance use treatment, suggest the need to expand access for drug and alcohol treatment programs overall, and in particular through the criminal justice system to reduce alcohol-related harms among PLWH who use drugs.

The FASTER-BUP Study, Extended-Release Injectable Buprenorphine for the Treatment of Opioid Use Disorder Among Individuals at High Risk of Overdose: Protocol for an Observational Prospective Study

North America is facing an unprecedented public health emergency of opioid-related morbidity and mortality. The mortality benefits of oral medication treatment for opioid use disorder (MOUD), such as methadone or buprenorphine, are well documented. However, barriers to access and long-term engagement have prevented maximizing their benefits. Long-acting injectable buprenorphine formulations were developed to address some of the challenges associated with oral MOUD. The "Pilot study to assess the feasibility, efficacy, and safety of extended-release injectable buprenorphine for the treatment of opioid use disorder among individuals at high risk of overdose" (FASTER-BUP) was developed to explore this treatment option in populations at high risk of overdose in a real-world Canadian setting. FASTER-BUP is a 24-week observational prospective study evaluating the feasibility and clinical utility of extended-release injectable buprenorphine (XR-BUP) for the treatment of opioid use disorder (OUD) among 40 adults at high risk of overdose (ie, lifetime history of overdose or a positive urine drug test (UDT) for fentanyl within 30 days prior to screening) in Vancouver, BC. The primary outcome is retention in treatment and secondary outcomes include: use of unregulated opioids, safety, overdose events, treatment satisfaction, changes in drug-related problems, changes in quality of life, opioid cravings, health service utilization, and criminal activity. FASTER-BUP is the first study to explore XR-BUP among individuals at high risk of overdose in a real-world Canadian setting. This commentary provides a brief narrative about the study thus far and presents insights on key adaptations to the study protocol, including those adopted to mitigate recruitment challenges.

Safety and Efficacy of Rapid Methadone Titration for Opioid Use Disorder in an Inpatient Setting: A Retrospective Cohort Study

OBJECTIVES

Inpatient guidelines for methadone titration do not exist, whereas outpatient guidelines lack flexibility and do not consider individual opioid tolerance. The evaluation of rapid, adaptable titration protocols may allow more patient-centered and effective treatment for opioid use disorder in the fentanyl era.

METHODS

This study performed a retrospective chart review of patients 18 years or older with opioid use disorder who were initiated on methadone at a single academic urban hospital using a rapid divided dose protocol between November 2019 and November 2020. The primary outcome was adverse events associated with methadone, specifically opioid toxicity or sedation requiring increased medical observation or intervention. The secondary outcome was total daily dose of methadone received on day 7 of titration.

RESULTS

Ninety-eight patients were included for a total of 168 visits. Sixty-five (66%) were male, with a median age of 38 years (interquartile range, 31-42 years). Sedation occurred in 2 patients (1%), who required either naloxone administration or transfer to an intensive care unit for monitoring. Of the 135 visits where patients received at least 7 days of methadone, the mean dose on day 1 was 41 mg (SD, 9.6 mg) and on day 7 was 65 mg (SD, 20.9 mg).

CONCLUSIONS

In this inpatient cohort, rapid methadone titration was well tolerated and resulted in patients reaching higher doses of methadone than would be possible with a standard schedule, with few adverse events. Given the known effective dose range, this approach may result in shorter time to clinical stabilization and suggests that alternative methadone titration schedules may be safe and effective in appropriately selected patients.

Using a cascade of care framework to identify gaps in access to medications for alcohol use disorder in British Columbia, Canada

BACKGROUND AND AIMS

Despite the significant burden of alcohol use disorder (AUD) and availability of safe and effective medications for AUD (MAUD), population-level estimates of access and engagement in AUD-related care are limited. The aims of this study were to generate a cascade of care for AUD in British Columbia (BC), Canada, and to estimate the impacts of MAUD on health outcomes.

DESIGN

This was a retrospective population-based cohort study using linked administrative health data.

SETTING

British Columbia, Canada, 2015-2019.

PARTICIPANTS

Using a 20% random sample of BC residents, we identified 7231 people with moderate-to-severe alcohol use disorder (PWAUD; overall prevalence = 0.7%).

MEASUREMENTS

We developed a six-stage AUD cascade (from diagnosis to ≥6 months retention in MAUD) among PWAUD. We evaluated trends over time and estimated the impacts of access to MAUD on AUD-related hospitalizations, emergency department visits and death.

FINDINGS

Between 2015 and 2019, linkage to AUD-related care decreased (from 80.4% to 46.5%). However, rates of MAUD initiation (11.4% to 24.1%) and retention for ≥1 (7.0% to 18.2%), ≥3 (1.2% to 4.3%) or ≥6 months (0.2% to 1.6%) increased significantly. In adjusted analyses, access to MAUD was associated with reduced odds of experiencing any AUD-related adverse outcomes, with longer retention in MAUD showing a trend to greater odds reduction: adjusted odds ratio (95% CI) ranging from 0.59 (0.48-0.71) for MAUD retention <1 month to 0.37 (0.21-0.67) for ≥6 months retention.

CONCLUSIONS

Access to medications for alcohol use disorder among people with moderate-to-severe alcohol use disorder in British Colombia, Canada increased between 2015 and 2019; however, initiation and retention remained low. There was a trend between longer retention in medications for alcohol use disorder and greater reductions in the odds of experiencing alcohol use disorder-related adverse outcomes.

Cytisine for smoking cessation: A systematic review and meta-analysis

BACKGROUND

Cytisine is a smoking cessation medication. This systematic review incorporates recently published randomized controlled trials (RCTs) to provide an updated evidence-based assessment of cytisine's efficacy and safety.

METHODS

We searched Cochrane Library, MEDLINE, and EMBASE, for RCTs comparing cytisine to other smoking cessation treatments in adults who smoke.

PRIMARY OUTCOME

6-month biochemically verified continuous abstinence. Other outcomes: abstinence at longest follow-up, adverse events, mortality, and health-related quality of life (HRQOL). We used Grading of Recommendations Assessment, Development and Evaluation (GRADE) to assess evidence certainty.

RESULTS

We included 14 RCTs involving 9953 adults. Cytisine was superior to placebo (risk ratio [RR] 2.25, 95% confidence interval [CI] 1.13-4.47; 5 RCTs, 4325 participants), but not varenicline (RR 1.13, 95% CI 0.65-1.95; 2 RCTs, 2131 participants) for the primary outcome. Cytisine was superior to placebo (RR 2.78, 95% CI 1.64-4.70; 8 RCTs, 5762 participants) and nicotine replacement therapy [NRT] (RR 1.39, 95% CI 1.12-1.73; 2 RCTs, 1511 participants), but not varenicline (RR 1.02, 95% CI 0.72-1.44; 4 RCTs, 2708 participants) for abstinence at longest follow-up. Cytisine increased mostly gastrointestinal adverse events compared to placebo (RR 1.15; 95% CI 1.06-1.25; 8 RCTs, 5520 participants) and NRT (RR 1.52, 95% CI 1.26-1.84; 1 RCT, 1310 participants) but less adverse events compared to varenicline (RR 0.67; 95% CI 0.48-0.95; 3 RCTs, 2484 participants).

CONCLUSION

Cytisine shows greater efficacy than placebo and NRT, but more adverse events. It is comparable to varenicline, with fewer adverse events. This can inform clinicians and guidelines on cytisine for smoking cessation.

Trends in cocaine and crystal methamphetamine injection over time in a Canadian setting between 2008 and 2018

OBJECTIVE

Unregulated stimulant use is rising globally, though trends in use of cocaine and crystal methamphetamine (CM), the two most commonly used unregulated stimulants in North America, are poorly characterized in many settings. In this study we examined patterns and associations between the injection of cocaine and CM over time in an urban Canadian setting.

METHODS

The study collected data from two prospective cohorts of people who inject drugs in Vancouver, Canada, between 2008 and 2018. We applied a time series analysis, using multivariable linear regression to detect relationships between reported CM and cocaine injection and year, controlling for covariates. The study used cross-correlation to evaluate the relative trajectories of each substance over time.

RESULTS

Among 2056 participants, per annum rates of reported injection cocaine use declined significantly over the duration of this study from 45 % to 18 % (p < 0.001), while rates of CM injection increased from 17 % to 32 % (p < 0.001). Multivariable linear regression showed that recent CM injection was negatively associated with recent cocaine injection (β = -0.609, 95 % CI = -0.750, -0.467). Cross-correlation demonstrated that injection CM use was associated with a decrease in the likelihood of cocaine injection 12 months later (p = 0.002).

CONCLUSIONS

These findings demonstrate an epidemiological shift in patterns of injection stimulant use, with rising CM injection associated with a corresponding decrease in cocaine injection over time. Strategies are urgently needed that help to treat and reduce harm among the growing population of people who inject CM.

Impacts of the COVID-19 pandemic on enrollment in medications for opioid use disorder (MOUD) in Vancouver, Canada: An interrupted time series analysis

BACKGROUND

In anticipation of COVID-19 related disruptions to opioid use disorder (OUD) care, new provincial and federal guidance for the management of OUD and risk mitigation guidance (RMG) for prescription of pharmaceutical opioids were introduced in British Columbia, Canada, in March 2020. This study evaluated the combined impacts of the COVID-19 pandemic and counteracting OUD policies on enrollment in medications for OUD (MOUD).

METHODS

Using data from three cohorts of people with presumed OUD in Vancouver, we conducted an interrupted time series analysis to estimate the combined effects impact of the COVID-19 pandemic and counteracting OUD policies on the prevalence of enrollment in MOUD overall, as well as in individual MOUDs (methadone, buprenorphine/naloxone, slow-release oral morphine) between November 2018 and November 2021, controlling for pre-existing trends. In sub-analysis we considered RMG opioids together with MOUD.

RESULTS

We included 760 participants with presumed OUD. In the post-COVID-19 period, MOUD and slow-release oral morphine prevalence rates showed an estimated immediate increase in level (+7.6%, 95% CI: 0.6%, 14.6% and 1.8%, 95% CI: 0.3%, 3.3%, respectively), followed by a decline in the monthly trend (-0.8% per month, 95% CI: -1.4%, -0.2% and -0.2% per month, 95% CI: -0.4, -0.1, respectively). There were no significant changes in the prevalence trends of enrollment in methadone, buprenorphine/naloxone, or when RMG opioids were considered together with MOUD.

CONCLUSIONS

Despite immediate improvements in MOUD enrollment in the post-COVID-19 period, this beneficial trend reversed over time. RMG opioids appeared to have provided additional benefits to sustain retention in OUD care.

Experiencing homelessness and progression through the HIV cascade of care among people who use drugs

OBJECTIVE

To investigate the longitudinal association between periods of homelessness and progression through the HIV cascade of care among people who use drugs (PWUD) with universal access to no-cost HIV treatment and care.

DESIGN

Prospective cohort study.

METHODS

Data were analysed from the ACCESS study, including systematic HIV clinical monitoring and a confidential linkage to comprehensive antiretroviral therapy (ART) dispensation records. We used cumulative link mixed-effects models to estimate the longitudinal relationship between periods of homelessness and progression though the HIV cascade of care.

RESULTS

Between 2005 and 2019, 947 people living with HIV were enrolled in the ACCESS study and 304 (32.1%) reported being homeless at baseline. Homelessness was negatively associated with overall progression through the HIV cascade of care [adjusted partial proportional odds ratio (APPO) = 0.56, 95% confidence interval (CI): 0.49-0.63]. Homelessness was significantly associated with lower odds of progressing to each subsequent stage of the HIV care cascade, with the exception of initial linkage to care.

CONCLUSIONS

Homelessness was associated with a 44% decrease in the odds of overall progression through the HIV cascade of care, and a 41-54% decrease in the odds of receiving ART, being adherent to ART and achieving viral load suppression. These findings support calls for the integration of services to address intersecting challenges of HIV, substance use and homelessness among marginalized populations such as PWUD.

Women's experiences in injectable opioid agonist treatment programs in Vancouver, Canada

BACKGROUND

Injectable opioid agonist treatment (iOAT) has recently been expanded in some geographical contexts in Canada as part of a response to the escalating overdose crisis. Complex gendered dynamics, including power differentials, violence, and social norms, shape the overdose crisis and drug treatment programs which can adversely impact women's experiences. This qualitative study examines how social (e.g., gender, income, housing) and structural factors (e.g., program policies) impact women's experiences of iOAT.

METHODS

Qualitative interviews were completed with 16 women enrolled in four iOAT programs in Vancouver, Canada. Approximately 50 hours of ethnographic observations were conducted. Interview transcripts and ethnographic fieldnotes were analyzed using a critical feminist lens by applying the concepts of embodiment, relationality, and social control to understand women's engagement and self-reported treatment outcomes.

RESULTS

Initial iOAT engagement was a relational process, including initiating treatment with a partner and engaging with iOAT to (re)build personal relationships. Relationships with iOAT providers, including flexibility and support with medication administration, were important to women, providing an affirming embodied experience and a greater sense of agency. However, program operations (e.g., mandated daily attendance, program crowding) incompatible with women's needs (e.g., employment) could undermine these positive experiences. Women's reported outcomes highlight a tension between achieving more agency and the constraints of intensive and stigmatized treatment.

CONCLUSION

This study highlights how iOAT is both a source of care and control for women from a relational and embodied perspective. Findings underscore the need for gender-attentive and flexible drug treatment services to meet the varied needs of women and the importance of providing relational care for women accessing iOAT.

Perceived Mistreatment in Health Care Settings and its Relationship with HIV Clinical Outcomes in HIV-positive People who Use Drugs in Vancouver, Canada

People living with HIV (PLWH) often experience stigma and discrimination by health care professionals. We investigated the prevalence of perceived mistreatment in health care settings and its associations with HIV clinical outcomes and health care-seeking behaviour using data from a long-running prospective cohort of PLWH who use drugs. Of the 857 participants included, 19% reported at least one instance of perceived mistreatment during the study period. In adjusted longitudinal analyses, perceived mistreatment was positively associated with not being on ART in the same follow-up period, and participants who reported perceived mistreatment were less likely to report seeing a physician in the subsequent follow-up period. Daily use of injection drugs was positively associated with reporting perceived mistreatment. These findings demonstrate the implications of negative health care interactions in a population that must consistently engage with the health care system, and the need for stigma-reducing educational interventions for health care professionals.

Re-incarceration and associated social, structural and behavioural factors among people who use drugs in an urban Canadian setting

BACKGROUND

People who use drugs (PWUD) are disproportionately incarcerated, however little is known about specific substance use, social and structural factors associated with re-incarceration among PWUD. We aimed to identify the socio-structural and substance use factors associated with re-incarceration among structurally-marginalized PWUD.

METHODS

We used longitudinal data from two prospective cohorts of PWUD in Vancouver, Canada. We included adults reporting at least one incarceration event in the last six months and who completed at least one additional follow-up study visit. We performed multivariable extended Cox regression to explore factors associated with re-incarceration.

RESULTS

Among 468 eligible participants, the median age was 40 years (Q1-Q3 = 34-46 years), 346 (73.9%) were men, 177 (37.8%) identified as Indigenous, and 227 (48.5%) experienced at least one re-incarceration event. Incidence rate of re-incarceration was 157 incarceration events per 1000 person years. In multivariable analyses, homelessness (adjusted hazard ratio [AHR] = 2.17; 95% confidence interval [95% CI]: 1.79-2.61), community judicial supervision (AHR = 3.89; 95% CI: 3.21-4.71) and re-incarceration during the study period (once: AHR = 1.95, 95% CI: 1.55-2.44; two or more events: AHR = 1.53, 95% CI: 1.23-1.90) were positively associated with re-incarceration. Among substance use variables that included illicit drugs, only heavy alcohol use remained significantly associated with re-incarceration across analyses after adjustment (AHR = 1.32; 95% CI: 1.06-1.65). Engagement in addiction treatment (AHR = 0.63; 95% CI: 0.53-0.75), mental illness (AHR = 0.70; 95% CI: 0.59-0.84) and age (AHR = 0.96; 95% CI: 0.95-0.97) were negatively associated with re-incarceration.

CONCLUSION

Access to housing and substance use services, including treatment for alcohol use disorder, following incarceration may reduce re-incarceration among PWUD. The high rates of re-incarceration of PWUD in our sample underscores how structural factors-such as homelessness and criminalization of substance use-drive re-incarceration among PWUD.

Increasing trends and incidence of nonfatal overdose among women sex workers who use drugs in British Columbia: The role of criminalization-related barriers to harm reduction

BACKGROUND

Structurally marginalized women who use drugs experience disproportionately elevated health and social inequities that require specialized responses to mitigate risk of overdose. This study aimed to longitudinally investigate incidence and predictors of first nonfatal overdose among women sex workers who use drugs.

METHODS

Data (2010-2019) were drawn from AESHA (An Evaluation of Sex Workers Health Access), a community-based, prospective, open cohort of > 900 women sex workers in Metro Vancouver, Canada. Incidence was examined and Cox regression modelled time-updated predictors of first nonfatal overdose. Time series analysis examined annual trends.

RESULTS

Among 273 eligible participants, 23% (n = 63) reported a first nonfatal overdose over follow-up with an incidence density of 5.87/100 person-years. In multivariable analysis, independent predictors of time to nonfatal overdose were police-related barriers to harm reduction (Adjusted Hazard Ratio [AHR]=2.62; 95% confidence interval [CI] 1.51-4.54), binge alcohol use (AHR=2.28; 95%CI 1.16-4.45), opioid use (AHR=2.23; 95%CI 1.15-4.33), and crystal methamphetamine use (AHR=2.07; 95%CI 1.27-3.39). Time series analysis demonstrated a significantly increasing trend in first nonfatal overdose, with annual proportions increasing 0.59% (95%CI 0.39-0.78%) every year, on average.

CONCLUSIONS

This study provides strong longitudinal evidence from the longest-standing cohort of sex workers in North America. Nonfatal overdose in this setting is a critical public health concern. Criminalization-related barriers to harm reduction strongly predicted nonfatal overdose. Structural changes to legal and policing practices alongside gender-sensitive addiction services are urgently needed.

Association of sex work and social-structural factors with non-fatal overdose among women who use drugs in Vancouver, Canada

BACKGROUND

Women who use drugs (WWUD) and engage in sex work experience disproportionate sex- and drug-related harms, such as HIV, however comparatively little is known about their overdose risk. Therefore, we examined the association between sex work and overdose and secondarily explored the association of social-structural factors, such as policing and gendered violence, with overdose.

METHODS

Data were derived from two community cohort studies based in Vancouver, Canada between 2005 to 2018. We used logistic regression with GEE to examine the associations between a) sex work and nonfatal overdose and b) social-structural and individual variables with overdose among WWUD who engaged in sex work during the study. Sex work, overdose, and other variables were time-updated, captured every six months.

RESULTS

Among 857 WWUD included, 56% engaged in sex work during the study. Forty-three percent of WWUD engaged in sex work had at least one overdose compared to 26% of WWUD who did not. Sex work was not significantly associated with an increased odds of overdose (AOR = 1.14, 95% CI: 0.93-1.40). In the exploratory analysis amongst 476 WWUD engaged in sex work, social-structural variables associated with overdose in the multivariable model included exposure to: punitive policing (OR = 1.97, 95% CI: 1.30-2.96) and physical or sexual violence (OR = 2.55, 95% CI: 1.88-3.46).

CONCLUSIONS

WWUD engaged in sex work had an increased overdose burden that may be driven by social-structural factors rather than sex work itself. Interventions that address policing and gendered violence represent potential targets for effective overdose prevention.

The Cannabis-Dependent Relationship Between Methadone Treatment Dose and Illicit Opioid Use in a Community-Based Cohort of People Who Use Drugs

Background: Methadone maintenance treatment (MMT) is an effective treatment for opioid use disorder. However, subtherapeutic dosing may lead to continued opioid use by failing to suppress opioid withdrawal and craving. Preclinical and pilot experimental research suggests that cannabinoids may reduce opioid withdrawal and craving. We sought to test whether the association between low methadone dose and illicit opioid use differs according to concurrent cannabis use patterns. Methods: Data for this study were derived from two community-recruited cohorts of people (≥18 years old) who use illicit drugs in Vancouver, Canada. We used generalized estimating equations to estimate the adjusted association between lower daily MMT dose (<90 mg/day) and daily illicit opioid use, testing for interaction between dose and daily cannabis use. Results: Between December 2005 and December 2018, 1389 participants reported MMT enrolment and were included in the study. We observed a significant interaction (p<0.01) between daily cannabis and lower MMT dose on concurrent daily illicit opioid use: lower MMT doses increased the odds of daily illicit opioid use by 86% (adjusted odds ratio [AOR]=1.86, 95% confidence interval [CI]=1.61-2.16) during periods of no or low-frequency cannabis use and by 30% during periods of daily cannabis use (AOR=1.30, 95% CI=1.01-1.67). Discussion: This study provides preliminary observational evidence that cannabis may mitigate some of the negative effects of subtherapeutic MMT dosing, guiding future clinical investigations into the safety and efficacy of cannabis and cannabinoids as adjunct treatment for MMT.

Methadone Dose, Cannabis Use, and Treatment Retention: Findings From a Community-based Sample of People Who Use Unregulated Drugs

OBJECTIVES

Lower daily methadone dose is negatively associated with retention in methadone maintenance treatment (MMT). Cannabis use during MMT is common, with many patients reporting its use for opioid withdrawal mitigation. We sought to test whether the association between lower MMT dose and treatment retention differs by concurrent high-frequency cannabis use in a community sample of people on MMT.

METHODS

We obtained data from participants initiating MMT in 2 community-recruited prospective cohorts of people who use drugs in Vancouver, Canada. We built multivariable Cox frailty models to estimate the relationships between MMT dose (<90 mg/d vs ≥90 mg/d) and time to treatment discontinuation. We included an interaction term to test whether high-frequency (≥daily) cannabis use modified the measured effect of lower treatment dose on treatment retention.

RESULTS

Between December 2005 and December 2018, 829 participants (54.1%) initiated at least 1 MMT episode and were included in the analysis. Lower MMT dose was strongly positively associated with treatment discontinuation regardless of concurrent high-frequency cannabis use (interaction P > 0.05). Structural factors including homelessness and incarceration were significantly and positively associated with treatment discontinuation.

CONCLUSIONS

Although we previously found the magnitude and strength of the relationship between lower MMT dose and high-frequency unregulated opioid use to be tempered during high-frequency cannabis use periods, this effect measure modification does not appear to translate to time retained in treatment. Cannabis-based interventions to promote retention in MMT are unlikely to produce long-term benefit without addressing external factors that place MMT patients at increased risk of treatment discontinuation.

Early Career Training in Addiction Medicine: A Qualitative Study with Health Professions Trainees Following a Specialized Training Program in a Canadian Setting

Background: There has been a notable deficiency in the implementation of addiction science in clinical practice and many healthcare providers feel unprepared to treat patients with substance use disorders (SUD) following training. However, the perceptions of addiction medicine training by learners in health professions have not been fully investigated. This qualitative study explored perceptions of prior training in SUD care among early-career trainees enrolled in Addiction Medicine fellowships and electives in Vancouver, Canada. Methods: From April 2015 - August 2018, we interviewed 45 early-career physicians, social workers, nurses, and 17 medical students participating in training in addiction medicine. We coded transcripts inductively using qualitative data analysis software (NVivo 11.4.3). Results: Findings revealed six key themes related to early-career training in addiction medicine: (1) Insufficient time spent on addiction education, (2) A need for more structured addictions training, (3) Insufficient hands-on clinical training and skill development, (4) Lack of patient-centeredness and empathy in the training environment, (5) Insufficient implementation of evidence-based medicine, and (6) Prevailing stigmas toward addiction medicine. Conclusion: Early clinical training in addiction medicine appears insufficient and largely focused on symptoms, rather than etiology or evidence. Early career learners in health professions perceived benefit to expanding access to quality education and reported positive learning outcomes after completing structured training programs.

Crack cocaine use frequency is associated with HIV disease severity independent of antiretroviral therapy exposure: a prospective cohort study

We sought to evaluate the effect of crack cocaine use frequency on HIV disease severity among HIV-positive people who use unregulated drugs (PWUD). We analyzed data from the ACCESS study, an open prospective cohort of HIV-positive PWUD including comprehensive HIV clinical monitoring in a setting with no-cost healthcare. Multivariable generalized linear mixed-effects models were used to estimate the independent effect of time-updated crack cocaine use frequency on HIV disease severity, adjusting for ART exposure and relevant confounders. In multivariable adjusted models, daily or greater frequency of crack cocaine use was significantly associated with higher VACS Index scores (β = 0.8, 95% confidence interval: 0.1, 1.5) as compared to none. Our finding suggests that daily or greater frequency of crack cocaine use exacerbates HIV disease severity independent of ART exposure. The observed effect may reflect an underlying biological mechanism or other factors linked with crack cocaine use; further investigation is warranted.

"COVID just kind of opened a can of whoop-ass": The rapid growth of safer supply prescribing during the pandemic documented through an environmental scan of addiction and harm reduction services in Canada

OBJECTIVES

In the context of the ongoing overdose crisis, a stark increase in toxic drug deaths from the unregulated street supply accompanied the onset of the COVID-19 pandemic. Injectable opioid agonist treatment (iOAT - hydromorphone or medical-grade heroin), tablet-based iOAT (TiOAT), and safer supply prescribing are emerging interventions used to address this crisis in Canada. Given rapid clinical guidance and policy change to enable their local adoption, our objectives were to describe the state of these interventions before the pandemic, and to document and explain changes in implementation during the early pandemic response (March-May 2020).

METHODS

Surveys and interviews with healthcare providers comprised this mixed methods national environmental scan of iOAT, TiOAT, and safer supply across Canada at two time points. Quantitative data were summarized using descriptive statistics; interview data were coded and analyzed thematically.

RESULTS

103 sites in 6 Canadian provinces included 19 iOAT, 3 TiOAT and 21 safer supply sites on March 1, 2020; 60 new safer supply sites by May 1 represented a 285% increase. Most common substances were opioids, available at all sites; most common settings were addiction treatment programs and primary care clinics, and onsite pharmacies models. 79% of safer supply services were unfunded. Diversity in service delivery models demonstrated broad adaptability. Qualitative data reinforced the COVID-19 pandemic as the driving force behind scale-up.

DISCUSSION

Data confirmed the capacity for rapid scale-up of flexible, community-based safer supply prescribing during dual public health emergencies. Geographical, client demographic, and funding gaps highlight the need to target barriers to implementation, service delivery and sustainability.

Opioid agonist treatment improves progression through the HIV cascade of care among people living with HIV who use unregulated opioids

OBJECTIVES

Opioid agonist treatment (OAT) has been shown to improve certain HIV-related treatment measures among people with HIV (PHIV) with opioid use disorder (OUD). However, there is limited data on the impacts of OAT along the whole HIV cascade of care.

DESIGN AND METHODS

Using data from an ongoing cohort of PHIV who use drugs in Vancouver, Canada, we used cumulative link mixed-effects models to estimate the independent effect of OAT on achieving progressive steps in the HIV cascade among participants using unregulated opioids daily, after adjusting for confounders.

RESULTS

Between 2005 and 2017, we recruited 639 PHIV regularly using opioids (median age 42 years, 59% male, 56% White), of whom 70% were on OAT at their baseline visit. Engagement in OAT showed a nonsignificant trend with higher linkage to HIV care (adjusted partial proportional odds ratio [APPO] = 1.75, 95% confidence interval [CI]: 0.83-3.69), and significantly higher cumulative odds of successfully achieving subsequent HIV cascade steps: on ART (APPO = 3.85, 95% CI: 2.33-6.37); adherent to ART (APPO = 3.15, 95% CI: 2.15-4.62); and HIV viral suppression (APPO = 2.18, 95% CI: 1.51-3.14).

CONCLUSIONS

This study found a high level of OAT engagement among PHIV using unregulated opioids and that OAT engagement resulted in significantly increased progression through some of the higher steps of the HIV cascade. While these findings are encouraging, they highlight the need to reach populations off OAT to maximize the clinical and community-level benefits of ART.

The changing landscape of pharmaceutical alternatives to the unregulated drug supply during COVID-19

Background

The dual COVID-19 and overdose emergencies amplified strain on healthcare systems tasked with responding to both. One downstream consequence of the pandemic in the USA and Canada was a surge in drug overdoses resulting from public health-restricted access to services and an increasingly toxic unregulated drug supply. This study aimed to describe changes implemented by programs prescribing pharmaceutical alternatives to the drug supply during the early stages of the COVID-19 pandemic.

Methods

An environmental scan used surveys and qualitative interviews with service providers across Canada to examine pharmaceutical alternative prescribing practices and programs before and during the pandemic. This study summarized the nature, frequency, and reasons for pandemic-driven service delivery changes using directed content analysis, counts, and thematic analysis.

Results

Eighty-two of the 103 participating sites reported 1193 unique changes in physical space (368), client protocols (347), program operations (342), ancillary services (127), and staffing (90). Four qualitative themes describing the reasons for these changes emerged, namely (1) decreasing risk of COVID-19 infection; (2) decreasing risk of overdose; (3) prioritizing acute care of COVID-19 patients; and (4) improving client access to treatment.

Conclusions

While most changes were aimed at decreasing risk of COVID-19 infection, some were found to be at odds with the measures needed to combat the overdose crisis; others met dual objectives of decreased risk of both overdose and infection. Further research should examine which changes should be kept or reversed once COVID-19-related public health measures are lifted.

Periods of Homelessness Linked to Higher VACS Index Among HIV-Positive People Who Use Drugs

We sought to evaluate the impact of homelessness on HIV disease progression among people who use unregulated drugs (PWUD) living with HIV and test if this association was mediated by adherence to antiretroviral therapy (ART). We applied general linear mixed-effects modeling to estimate the longitudinal relationship between homelessness and the Veterans Aging Cohort Study (VACS) Index, a validated measure of HIV disease progression that predicts all-cause mortality, among a prospective cohort of PWUD. In a longitudinal model adjusted for ART adherence, homelessness was significantly associated with increased VACS Index scores and 16% of the association was mediated by ART adherence. These findings indicate that homelessness was a significant risk factor for HIV disease progression and this association was marginally mediated by ART adherence. Future studies are needed to quantify the other mechanisms (e.g., food insecurity, mental health) by which homelessness increases mortality risk among PWUD living with HIV.

The influence of poly-drug use patterns on the association between opioid agonist treatment engagement and injecting initiation assistance

BACKGROUND

Evidence suggests people who inject drugs (PWID) prescribed opioid agonist treatment (OAT) are less likely to provide injection drug use (IDU) initiation assistance. We investigated the association between OAT engagement and providing IDU initiation assistance across poly-drug use practices in Vancouver, Canada.

METHODS

Preventing Injecting by Modifying Existing Responses (PRIMER) is a prospective study seeking to identify structural interventions that reduce IDU initiation. We employed data from linked cohorts of PWID in Vancouver and extended the findings of a latent profile analysis (LPA). Multivariable logistic regression models were performed separately for the six poly-drug use LPA classes. The outcome was recently assisting others in IDU initiation; the independent variable was recent OAT engagement.

RESULTS

Among participants (n = 1218), 85 (7.0%) reported recently providing injection initiation assistance. When adjusting for age and sex, OAT engagement among those who reported a combination of high-frequency heroin and methamphetamine IDU and low-to-moderate-frequency prescription opioid IDU and methamphetamine non-injection drug use (NIDU) was associated with lower odds of IDU initiation assistance provision (Adjusted Odds Ratio [AOR]: 0.18, 95% CI: 0.05-0.63, P = 0.008). Significant associations were not detected among other LPA classes.

CONCLUSIONS

Our findings extend evidence suggesting that OAT may provide a population-level protective effect on the incidence of IDU initiation and suggest that this effect may be specific among PWID who engage in high-frequency methamphetamine and opioid use. Future research should seek to longitudinally investigate potential causal pathways explaining the association between OAT and initiation assistance provision among PWID to develop tailored intervention efforts.

Crystal methamphetamine use subgroups and associated addiction care access and overdose risk in a Canadian urban setting

OBJECTIVES

Methamphetamine use is rising globally and we have limited treatments for this. Subgroups within the diverse methamphetamine-using population may have distinct treatment needs. Among a community-recruited sample of people who use crystal methamphetamine, we aimed to identify subgroups and characterize their overdose risk and access to addiction care.

METHODS

Data from prospective cohorts of people who use drugs in Vancouver, Canada from 2014 to 2018 were used to conduct a repeated measures latent class analysis among participants who used crystal methamphetamine. Multivariable generalized estimating equations models were fit to determine the associated factors.

RESULTS

Among 824 eligible participants, a five-class model was identified as the best fit: (1) primary stimulant use (15.7%); (2) women engaged in sex work and opioid use (21.4%); (3) street income generation and opioid use (31.6%); (4) opioid agonist therapy (OAT) patients (22.3%); and (5) men who have sex with men (9.0%). In multivariable analyses, compared to the primary stimulant use group, non-fatal overdose was positively associated with street income generation (adjusted odds ratio [AOR] = 1.49, 95% confidence interval [95% CI]=1.30-1.71), sex work (AOR = 1.38, 95% CI=1.20-1.59) and OAT (AOR = 1.22, 95% CI=1.06-1.41) subgroups; engagement in non-OAT addiction care was negatively associated with street income generation (AOR = 0.81, 95% CI=0.68-0.97) and sex work (AOR = 0.78, 95% CI=0.63-0.98) subgroups.

DISCUSSION

Socioeconomically marginalized subgroups with opioid and crystal methamphetamine co-use were at highest risk of non-fatal overdose and had poorer access to addiction care, highlighting the need for tailored interventions.

Challenges with buprenorphine inductions in the context of the fentanyl overdose crisis: A case series

INTRODUCTION AND AIMS

North America is currently experiencing an epidemic of opioid overdose deaths, driven by the proliferation of fentanyl in the street drug market. Although buprenorphine/naloxone (BUP/NX) is an evidence-based, first-line opioid agonist for the management of opioid use disorder, a key challenge in its prescribing lies in the fact that it can precipitate opioid withdrawal during its initial induction process. At this time, there is minimal literature on the BUP/NX induction process in individuals who use illicit fentanyl regularly.

DESIGN, METHODS AND RESULTS

A case series from a Vancouver, Canada addiction medicine clinic of three fentanyl-exposed patients who experienced unexpected, precipitated withdrawal when initiating BUP/NX.

DISCUSSION AND CONCLUSION

These cases describe incidents of precipitated opioid withdrawal occurring after unusually long periods of fentanyl abstention. Although fentanyl is experienced as a short-acting opioid, the drug persists much longer in the body's peripheral tissues. Here, we highlight the new challenges fentanyl may pose to current BUP/NX induction strategies, and explore the possibility of a long-acting pharmacokinetic effect of fentanyl in the setting of repeated illicit use.

Impact of the international collaborative addiction medicine research fellowship on physicians' future engagement in addiction research

Background: To evaluate how an international one-year intensive research training program for addiction medicine physicians contributed to subsequent research involvement and productivity. Methods: We prospectively compared addiction medicine physician fellows admitted to a one-year training program with non-admitted controls, using baseline questionnaire and peer-reviewed publication data. Participants' publication activity was assessed from fellowship application date onwards using biomedical databases (e.g., PubMed, Embase). Results: Between July 2014 and June 2020, which is six years of cohorts, 56 (39 women) physicians, both fellows (n = 25) and non-admitted applicants (n = 31), were observed and included in the study, contributing 261 person-years of observation. At baseline, in the fellows' cohort: 76% of participants (19/25) reported past research involvement, 24% (6/25) had one or more advanced graduate degrees (e.g., MPH), and the median number of peer-reviewed, first author publications was one (Interquartile Range [IQR] = 0-2). At baseline, in the controls' cohort: 84% of participants (26/31) reported past research involvement, 39% (12/31) had one or more advanced graduate degrees, and the median number of peer-reviewed, first author publications was zero. The physicians' training included internal medicine (n = 8), family medicine (n = 33), psychiatry (n = 5) and others (n = 4). At follow up, there was a significant difference between fellows (n = 25) and controls (n = 31) in total number of publications (Rate Ratio [RR] = 13.09, 95% Confidence Interval [CI], 5.01 - 34.21, p < 0.001), as well as first author publications (RR = 5.59, 95% CI, 2.23 - 14.06, p < 0.001). Conclusion: In the six-year observation period, fellows' productivity indicates undertaking this fellowship was associated with significant research outputs in comparison to controls, signaling successful training of addiction physicians to help recruit addiction medicine physicians to participate in addiction research.

Inability to contact opioid agonist therapy prescribers during the COVID-19 pandemic in a Canadian setting: a cross-sectional analysis among people on opioid agonist therapy

BACKGROUND

The COVID-19 pandemic and consequent public health response may have undermined key responses to the protracted drug poisoning crisis, including reduced access to opioid agonist therapy (OAT) among people with opioid use disorder. Our study objectives were to estimate the prevalence of and identify factors associated with inability to contact OAT prescribers when in need among people on OAT in a Canadian setting during the dual public health crises.

METHODS

Survey data were collected from three prospective cohort studies of community-recruited people who use drugs between July and November 2020, in Vancouver, Canada. A multivariable logistic regression analysis was used to identify potential factors associated with inability to contact OAT prescribers among patients who accessed OAT in the past 6 months.

RESULTS

Among 448 respondents who reported accessing OAT in the past 6 months, including 231 (54.9%) men, 85 (19.0%) reported having been unable to contact OAT prescribers when needed, whereas 268 (59.8%) reported being able to talk to their prescriber when needed, and 95 (21.2%) reported that they did not want to talk to their medication prescriber in the previous 6 months. Among those who reported inability to contact prescribers, 45 (53.6%) reported that their overall ability to contact prescribers decreased since the start of the pandemic. In multivariable analyses, factors independently associated with inability to talk to OAT prescribers included: chronic pain (Adjusted Odds Ratio [AOR] = 1.82; 95% Confidence Interval [CI] 1.02, 3.27), moderate to severe symptoms of depression or anxiety (AOR = 4.74; 95% CI 2.30, 9.76), inability to access health/social services (AOR = 2.66; 95% CI 1.41, 5.02), and inability to self-isolate or socially distance most or all of the time (AOR = 2.13; 95% CI 1.10, 4.14).

CONCLUSIONS

Overall, approximately one fifth of the sample reported inability to contact their OAT prescribers when needed, and those people were more likely to have co-occurring vulnerabilities (i.e., co-morbidities, inability to access health/social services) and higher vulnerability to COVID-19. Interventions are needed to ensure optimal access to OAT and mitigate the deepening health inequities resulting from the COVID-19 pandemic and the escalating drug poisoning crisis.

Prevalence and longitudinal correlates of recent exposure to fentanyl among HIV-positive people who use unregulated drugs during a community-wide overdose crisis

The United States and Canada are experiencing an opioid overdose crisis driven largely by exposure to fentanyl (a potent synthetic opioid), with little known about fentanyl exposure among HIV-positive people who use unregulated drugs (PWUD). We sought to estimate the prevalence and correlates of fentanyl exposure among a community-recruited sample derived from a prospective cohort study of HIV-positive PWUD in Vancouver, Canada. Generalized linear mixed-effects analyses were used to identify longitudinal factors associated with a fentanyl-positive urine drug screen test. Between June 2016-November 2017, 456 participants were recruited and contributed 1007 observations. At baseline, 96% of participants were ART-exposed, 72% had an HIV viral load (VL) <50 copies/mL and 21% had a fentanyl-positive test. Longitudinally, fentanyl-positive tests were characterized by: younger participant age (Adjusted Odds Ratio [AOR] = 0.45), recent non-fatal overdose (AOR = 2.30), engagement in opioid agonist therapy (AOR = 1.91), and at least daily heroin injection (AOR = 11.27). CD4+ cell count was negatively associated with fentanyl urine positivity (AOR = 0.92) (all p < 0.05). We identified several risk factors for overdose linked to fentanyl exposure among this sample, although no link with HIV treatment engagement or detectable HIV VL. Innovative strategies are needed to reduce the harmful effects of the contaminated unregulated drug supply experienced by PWUD.

Buprenorphine/naloxone associated with a reduced odds of fentanyl exposure among a cohort of people who use drugs in Vancouver, Canada

BACKGROUND

Little is known about the relationship between opioid agonist therapy (OAT) and fentanyl use, specifically. This study aimed to estimate the association between current use of different forms of OAT, including methadone, buprenorphine/naloxone (BUP/NX), slow release oral morphine (SROM), or injectable opioid agonist treatment (iOAT), and the likelihood of a fentanyl-positive urine drug test (UDT) as compared to no OAT.

METHODS

Data were obtained from three community-recruited prospective cohort studies of people who use drugs in Vancouver, Canada from December 2016 through November 2018. Using multivariable Generalized Estimating Equations (GEE), we examined the association between current use of each form of OAT, as compared to no OAT, and fentanyl-positive UDT among participants who use opioids.

RESULTS

The 915 participants contributed 2112 UDTs over a median of two follow-up visits. The majority of UDTs (74.9 %) were positive for fentanyl. After adjustment for a priori defined confounding factors, compared to no OAT, current use of BUP/NX was associated with lower odds of fentanyl-positive UDT (odds ratio [OR] = 0.36, 95 % confidence interval [CI]: 0.22-0.58) while current use of methadone (OR = 0.84, 95 % CI: 0.65-1.07), iOAT (OR = 1.30, 95 % CI: 0.75-2.28), and SROM (OR = 1.34, 95 % CI: 0.74-2.43) were not.

CONCLUSIONS

In this cohort of people who use opioids in Vancouver, only use of BUP/NX was associated with lower odds of fentanyl-positive UDT. Our findings highlight high rates of ongoing fentanyl use despite the use of OAT and support the expansion of BUP/NX for the treatment of people who use fentanyl.

Outcomes of Ottawa, Canada's Managed Opioid Program (MOP) where supervised injectable hydromorphone was paired with assisted housing

BACKGROUND

The Ottawa Inner City Health's Managed Opioid Program is the first, to our knowledge, to pair injectable opioid agonist hydromorphone treatment with assisted housing for people experiencing homelessness with severe opioid use disorder (OUD) and injection drug use. We aimed to describe this program and evaluate retention, health, and social wellbeing outcomes.

METHODS

We retrospectively assessed the first cohort of clients enrolled in the Managed Opioid Program between August 2017-2018. The primary outcome was retention at 12 months. Secondary outcomes included injectable and oral opioid dose titration, non-prescribed opioid use, overdoses, connection with behavioural health services, and social well-being. Descriptive statistics were used to summarize baseline demographics and secondary outcomes. Actuarial survival analysis was used to assess retention among participants.

RESULTS

The study sample included 26 participants: median age was 36 years, 14 were female, 22 were White, eight had alcohol use disorders, 25 had stimulant use disorders, and all had a history of concurrent psychiatric illness. Retention at 12 months was 77% (95% CI 62-95). Throughout the first-year participants' opioid treatment doses increased. The median daily dose of injectable hydromorphone was 36 mg [17-54 mg] and 156 mg [108-188 mg] at enrollment and one year respectively. The median daily dose of oral opioid treatment was 120-milligram morphine equivalents [83-180 mg morphine equivalents] and 330-milligram morphine equivalents [285-428 mg morphine equivalents] at enrollment and one year respectively. Over half had no overdoses and there were no deaths among participants who remained enrolled. At one year, 45% stopped non-prescribed opioid use, 96% connected to behavioral health services, 73% reconnected with estranged families, and 31% started work or vocational programs.

CONCLUSION

Individuals with severe OUD engaged in injectable hydromorphone treatment and housing showed high retention in care and substantive improvements in patient-centered health and social well-being outcomes.

The Veterans Aging Cohort Study (VACS) Index Predicts Mortality in a Community-recruited Cohort of People With Human Immunodeficiency Virus (HIV) Who Use Illicit Drugs

The Veterans Aging Cohort Study (VACS) index combines commonly collected clinical biomarkers to estimate human immunodeficiency virus (HIV) disease severity. Among a prospective cohort of people living with HIV who use illicit drugs (PWUD) (n = 948), we found that the VACS index was significantly associated with mortality over a 20-year study period.

Building a hospital-based addiction medicine consultation service in Vancouver, Canada: the path taken and lessons learned

BACKGROUND AND AIMS

To improve evidence-based addiction care in acute care settings, many hospitals across North America are developing an inpatient addiction medicine consultation service (AMCS). St Paul's Hospital in Vancouver, Canada houses a large interdisciplinary AMCS. This study aimed to: (1) describe the current model of clinical care and its evolution over time; (2) evaluate requests for an AMCS consultation over time; (3) highlight the established clinical training opportunities and educational curriculum and (4) provide some lessons learned.

DESIGN, SETTING AND PARTICIPANTS

A retrospective observational analysis in an urban, academic hospital in Vancouver, Canada with a large interdisciplinary AMCS, studied from 2013 to 2018, among individuals who presented to hospital and had a substance use disorder.

MEASUREMENTS

Data were collected using the hospital's electronic medical records. The primary outcome was number of AMCS consultations over time.

FINDINGS

In 2014 the hospital's AMCS was restructured into an academic, interdisciplinary consultation service. A 228% increase in the number of consultations was observed between 2013 (1 year prior to restructuring) and 2018 (1373 versus 4507, respectively; P = 0.027). More than half of AMCS consultations originated from the emergency department, with this number increasing over time (55% in 2013 versus 74% in 2018). Referred patients were predominantly male (> 60% in all 5 years) between the ages of 45 and 65 years. Reasons for consultation remained consistent and included: opioids (33%), stimulants (30%), alcohol (23%) and cannabis use (8%).

CONCLUSIONS

After St Paul's Hospital in Vancouver, Canada was restructured in 2014 to a large, interdisciplinary addiction medicine consultation service (AMCS), the AMCS saw a 228% increase in the number of consultation requests with more than half of requests originating from the emergency department. Approximately two-thirds of consultation requests were for opioid or stimulant use.

The relationship between opioid agonist therapy satisfaction and fentanyl exposure in a Canadian setting

Background

While patient-reported treatment dissatisfaction is considered an important factor in determining the success of substance use disorder treatment, the levels of dissatisfaction with opioid agonist therapies (OAT) and its relationship with the risk of fentanyl exposure have not been characterized in the context of the ongoing opioid overdose crisis in the US and Canada. Our primary hypothesis was that OAT dissatisfaction was associated with an increased odds of fentanyl exposure.

Methods

Our objective was to examine self-reported treatment satisfaction among OAT patients in Vancouver, Canada and the association with fentanyl exposure. Longitudinal data were derived from 804 participants on OAT enrolled in two community-recruited harmonized prospective cohort studies of people who use drugs in Vancouver between 2016 and 2018 via semi-annual interviews and urine drug screens (UDS). We employed multivariable generalized estimating equations to examine the relationship between OAT dissatisfaction and fentanyl exposure.

Results

Out of 804 participants (57.0% male), 222 (27.6%) reported being dissatisfied with OAT at baseline and 1070 out of 1930 observations (55.4%) had fentanyl exposure. The distribution of OAT reported in the sample was methadone (n = 692, 77.7%), buprenorphine-naloxone (n = 82, 9.2%), injectable OAT (i.e., diacetylmorphine or hydromorphone; (n = 65, 7.3%), slow-release oral morphine (n = 44, 4.9%) and other/study medication (n = 8, 1.0%). In the multivariable analysis, OAT dissatisfaction was positively associated with fentanyl exposure (AOR = 1.34; 95% CI: 1.08–1.66).

Conclusions

A substantial proportion of OAT patients in our sample reported dissatisfaction with their OAT, and more than half were exposed to fentanyl. We also found that those who were dissatisfied with their OAT were more likely to be exposed to fentanyl. These findings demonstrate the importance of optimizing OAT satisfaction in the context of the ongoing opioid overdose crisis.

Service delivery models for injectable opioid agonist treatment in Canada: 2 sequential environmental scans

BACKGROUND

Injectable opioid agonist treatment (iOAT) is an emerging evidence-based option in the continuum of care for opioid use disorder in parts of Canada. Our study objective was to identify and describe iOAT programs operating during the ongoing opioid overdose crisis.

METHODS

We conducted 2 sequential environmental scans. Programs were eligible to participate if they were in operation as of Sept. 1, 2018, and Mar. 1, 2019. Information was collected over 2-3 months for each scan (September-October 2018, March-May 2019). Programs that participated in the first scan and newly established programs were invited to participate in the second scan. The scans included questions about location, service delivery model, clinical and operational characteristics, numbers and demographic characteristics of clients, and program barriers and facilitators. Descriptive analysis was performed.

RESULTS

We identified 14 unique programs across the 2 scans. Eleven programs located in urban centres in British Columbia and Ontario participated in the first scan. At the time of the second scan, 2 of these programs were on hold and 2 of 3 newly established programs were in Alberta. The total capacity of all participating programs was 420 clients at most. Four service delivery models were identified; iOAT was most commonly integrated within existing health and social services. All programs offered hydromorphone, and 1 program also offered diacetylmorphine. In the first scan, 73% of clients (133/183) were male; the mean age of clients was 47 years. Limited capacity, pharmacy operations and lack of diacetylmorphine access were among the most frequently reported barriers. The most commonly reported facilitators included client-centred care, client relationships and access to other health and social support.

INTERPRETATION

Evidence indicates that iOAT can be successfully implemented using diverse service delivery models. Future work should facilitate scale-up of this evidence-based treatment where gaps persist in high-risk communities.

Long term pre-treatment opioid use trajectories in relation to opioid agonist therapy outcomes among people who use drugs in a Canadian setting

BACKGROUND

Opioid agonist therapy (OAT) models are generally provided without consideration of how pre-treatment characteristics may be associated with outcome. Therefore, we aimed to first characterize longitudinal trajectories of opioid use before initiating OAT. Then we explored the impact of OAT on opioid use across these pre-treatment trajectories.

METHODS

Data were derived from three prospective cohort studies involving people who use drugs in Vancouver, Canada. Latent class growth analysis was applied to identify opioid use trajectories based on individual-level observations three years before starting OAT. Multivariable generalized linear mixed model was used to examine whether engaging in OAT was associated with lower risk of illicit opioid use among participants with different pre-treatment opioid use trajectories.

RESULTS

464 participants were included in the study between September 2005 and November 2018. Two pre-treatment opioid use trajectories were identified: high frequency users (246, 53.0%) and gradually increasing frequency users (218, 47.0%). We observed different strengths of association between OAT engagement and illicit opioid use among high frequency users (adjusted odds ratio [AOR] = 0.36, 95% Confidence Interval [CI]: 0.20 - 0.63) and gradually increasing frequency users (AOR = 0.91, 95% CI: 0.53 - 1.56). Unstable housing, any stimulant use, experiencing violence, drug dealing, sex work involvement, and incarceration were independently and positively associated with ongoing illicit opioid use.

CONCLUSIONS

Distinct pre-treatment opioid use trajectories are likely to influence treatment outcomes. Research is required to determine if tailored strategies specific to people with different pre-treatment opioid use patterns have potential to improve outcomes of OAT.

Motivations to initiate injectable hydromorphone and diacetylmorphine treatment: A qualitative study of patient experiences in Vancouver, Canada

BACKGROUND

Within the context of the ongoing overdose crisis and limitations of conventional opioid treatments, the scale-up of injectable hydromorphone (HDM) and diacetylmorphine (DAM) as evidenced-based treatments is currently underway in some settings in Canada. Past research has underscored the importance of treatment initiation in shaping onward treatment trajectories, however structural factors that influence participants' motivations to access injectable HDM or DAM have not been fully characterized. This study examines peoples' motivations for accessing HDM/DAM treatment and situates these within the social and structural context that shapes treatment delivery by employing the concept of structural vulnerability.

METHODS

Fifty-two individuals enrolled in injectable HDM/DAM programs were recruited from four community-based clinical programs in Vancouver, Canada to participate in qualitative semi-structured interviews. Approximately 50 h of ethnographic fieldwork was also completed in one clinical setting, and one-on-one with participants public spaces. Interview transcripts and ethnographic fieldnotes were analyzed through a structural vulnerability lens with a focus on treatment initiation.

RESULTS

Participants' previous experiences and perceptions of other drug treatments (e.g. methadone) foregrounded their initiation of injectable HDM/DAM. Social and structural factors (e.g. fentanyl-adulterated drug supply, poverty, drug criminalization) influenced participants' motivations to address immediate physical risks and their initial perception of this treatment's ability to align with their opioid use experiences. Similar social and structural factors that drive immediate physical risks, were also evidenced in participants' motivations to make changes in their daily lives and to address broader opioid use goals.

CONCLUSION

Participants descriptions of their motivations to initiate HDM/DAM highlight how structural vulnerabilities shaped participants' experiences initiating injectable HDM/DAM.

Changes in drug use behaviors coinciding with the emergence of illicit fentanyl among people who use drugs in Vancouver, Canada

Background: With the emergence of illicitly-manufactured fentanyl, drug overdose deaths have risen in unprecedented numbers. In this context, there is an urgent need to characterize potential changes in drug use behaviors among people who use drugs (PWUD). Objective: To examine changes in drug use behaviors following the emergence of illicit fentanyl among people who use drugs (PWUD). Methods: Data for this cross-sectional analysis was derived from three prospective cohorts of PWUD between December 2016 and May 2017 in Vancouver, Canada. Multivariable logistic regression was used to determine factors associated with self-reported behavior changes (binary variable "yes" or "no") following the emergence of illicit fentanyl. Results: Among 999 participants [363 (36.3%) females], 388 (38.8%) reported some behavior change. The remaining 611 (61.2%) reported no change in behavior; 240 (39.3%) of these individuals had recently been exposed to fentanyl. In multivariable analyses, factors independently associated with behavior change included recent non-fatal overdose (Adjusted Odds Ratio [AOR] = 2.28), active injection drug use (AOR = 1.96), being on opioid agonist therapy (AOR = 1.80), and urine drug screen positive for fentanyl (AOR = 1.45), (all p < .05). Conclusion: The majority of PWUD in our sample did not change their drug use behavior despite a high prevalence of fentanyl exposure, indicating a need for targeted behavior change messaging and overdose prevention efforts such as naloxone and addiction treatment for this sub-population of PWUD. Further, the high fentanyl exposure observed in our sample suggests a need to address upstream structural factors shaping the overdose risk in addition to individual behavioral change.

Characterising the increasing prevalence of crystal methamphetamine use in Vancouver, Canada, from 2006-2017: A gender-based analysis

INTRODUCTION

Methamphetamine use is increasing in North America and is associated with numerous negative health effects and social harms. As drug-related harms are often gendered, this study sought to examine the differential impacts of gender on the trends, risk factors and health implications of crystal methamphetamine use among a Canadian cohort of people with high rates of injection polysubstance use.

METHODS

Data were collected from two prospective cohorts of people who inject drugs in Vancouver, Canada. We examined trends in reported crystal methamphetamine use from 2006-2017 using the Cochrane-Armitage test for trend. We used multivariable generalised estimating equations, stratified by gender, to determine independent risk factors and health outcomes associated with crystal methamphetamine use.

RESULTS

In total, 1984 participants were included in the study, including 694 (35%) women. The prevalence of reported crystal methamphetamine use within the previous 6 months rose from 19% in 2006 to 36% in 2017, with a rise seen in both genders (P < 0.001). Reported crystal methamphetamine use was associated with numerous risk behaviours and drug-related harms in both genders, and in women it was associated with an increase in experiences of sexual violence (adjusted odds ratio 1.64, 95% confidence interval 1.18, 2.27).

CONCLUSIONS

These findings demonstrate the rising prevalence of reported crystal methamphetamine use in Vancouver in a cohort with high rates of polysubstance use. This work highlights drug and sex-related risk behaviours associated with crystal methamphetamine use for both genders, and underscores the need to develop strategies to address the growing use of crystal methamphetamine.

Use of a novel prescribing approach for the treatment of opioid use disorder: Buprenorphine/naloxone micro-dosing - a case series

INTRODUCTION AND AIMS

Buprenorphine/naloxone is an evidence-based treatment for opioid use disorder, but an identified limitation is the period of required opioid abstinence prior to induction on the medication. 'Micro-dosing', or using incrementally increasing doses of buprenorphine/naloxone over time, may be a way to overcome this challenge as it can be done in parallel with the ongoing use of other opioids (either illicit or prescribed).

DESIGN AND METHODS

A retrospective case series (January to December 2018) was completed of seven participants who underwent buprenorphine/naloxone induction using micro-dosing at two outpatient addiction clinics in Vancouver, Canada.

RESULTS

Seven participants completed a 7-day buprenorphine/naloxone micro-dosing protocol. Prior to and during the induction, one participant was prescribed methadone, three were prescribed slow release oral morphine and three used only illicit fentanyl. Participants were prescribed sublingual buprenorphine/naloxone: 0.5 mg once daily (day 1), 0.5 mg twice daily (BID; day 2), 1 mg BID (day 3), 2 mg BID (day 4), 3 mg BID (day 5), 4 mg BID (day 6) and 12 mg once daily (day 7). On day 7, all prescribed or illicit full opioid agonists were discontinued. Buprenorphine/naloxone was subsequently titrated to a daily dose of between 12 and 32 mg. All patients reported success with buprenorphine/naloxone induction with no precipitated withdrawal.

DISCUSSION AND CONCLUSIONS

Buprenorphine/naloxone micro-dosing may offer a promising alternative approach for successful induction for individuals with opioid use disorder who desire treatment with buprenorphine/naloxone, and further research to determine effectiveness is warranted.

Treatment of stimulant use disorder: A systematic review of reviews

AIMS

Stimulant use disorder contributes to a substantial worldwide burden of disease, although evidence-based treatment options are limited. This systematic review of reviews aims to: (i) synthesize the available evidence on both psychosocial and pharmacological interventions for the treatment of stimulant use disorder; (ii) identify the most effective therapies to guide clinical practice, and (iii) highlight gaps for future study.

METHODS

A systematic database search was conducted to identify systematic reviews and meta-analyses. Eligible studies were those that followed standard systematic review methodology and assessed randomized controlled trials focused on the efficacy of interventions for stimulant use disorder. Articles were critically appraised using an assessment tool adapted from Palmeteer et al. and categorized for quality as 'core' or 'supplementary' reviews. Evidence from the included reviews were further synthesized according to pharmacological or non-pharmacological management themes.

RESULTS

Of 476 identified records, 29 systematic reviews examining eleven intervention modalities were included. The interventions identified include: contingency management, cognitive behavioural therapy, acupuncture, antidepressants, dopamine agonists, antipsychotics, anticonvulsants, disulfiram, opioid agonists, N-Acetylcysteine, and psychostimulants. There was sufficient evidence to support the efficacy of contingency management programs for treatment of stimulant use disorder. Psychostimulants, n-acetylcysteine, opioid agonist therapy, disulfiram and antidepressant pharmacological interventions were found to have insufficient evidence to support or discount their use. Results of this review do not support the use of all other treatment options.

CONCLUSIONS

The results of this review supports the use of contingency management interventions for the treatment of stimulant use disorder. Although evidence to date is insufficient to support the clinical use of psychostimulants, our results demonstrate potential for future research in this area. Given the urgent need for effective pharmacological treatments for stimulant use disorder, high-quality primary research focused on the role of psychostimulant medications for the treatment of stimulant use disorder is needed.

Behavioural, social and structural-level risk factors for developing AIDS among HIV-positive people who use injection drugs in a Canadian setting, 1996-2017

People who use injection drugs (PWID) experience high rates of HIV acquisition and, as a result of lower rates of optimal access and adherence to combination antiretroviral therapy (ART), experience worse HIV treatment outcomes than other key affected populations. However, the incidence and risk factors for the development of AIDS among HIV-positive PWID have not been completely described. We used data from a community-recruited prospective cohort of HIV-positive PWID in Vancouver, Canada, a setting with universal no-cost ART and a comprehensive clinical monitoring registry. We used multivariable extended Cox models to identify factors associated with time to AIDS. Between 1996 and 2017, 396 participants, including 140 (35.4%) women, were followed for a median of 39.0 months (interquartile range: 16.6-76.2), among whom 165 (41.7%) developed AIDS. In a multivariable model, homelessness (Adjusted Hazard Ratio [AHR] = 1.76 (1.18-2.61)) and injection drug use within the preceding six months (AHR = 1.74 (1.17-2.58)) were independently associated with a higher risk of developing AIDS. Despite widespread scale-up of programmes to improve ART utilization, significant risk factors for the development of AIDS remain among HIV-positive PWID in this setting.

Temporal changes in non-fatal opioid overdose patterns among people who use drugs in a Canadian setting

Background and Aims: Little is known about how the expansion of opioid agonist therapy (OAT) and emergence of fentanyl in the illicit drug supply in North America has influenced non-fatal opioid overdose (NFOD) risk. Therefore, we sought to identify patterns of substance use and addiction treatment engagement (i.e., OAT, other inpatient or outpatient treatment) prior to NFOD, as well as the trends and correlates of each pattern among people who use drugs (PWUD) in Vancouver, Canada. Methods: Data were derived from participants in three prospective cohorts of PWUD in Vancouver in 2009-2016. Observations from participants reporting opioid-related NFOD in the previous six months were included. A latent class analysis was used to identify classes based on substances used at the time of last NFOD and addiction treatment engagement in the month prior to the last NFOD. Multivariable generalized estimating equations estimated the correlates of each class membership. Results: In total, 889 observations from 570 participants were included. Four distinct classes were identified: (1) polysubstance use (PSU) and addiction treatment engagement; (2) PSU without treatment engagement; (3) exposure to unknown substances, mostly without treatment engagement; and (4) primary heroin users without treatment engagement. The class of exposure to unknown substances appeared in 2015 and became the dominant group (76.9%) in 2016. In multivariable analyses, the odds of membership in the class of primary heroin users decreased over time (adjusted odds ratio [AOR]: 0.74, 95% confidence interval [CI]: 0.68-0.81). Conclusions: Changing profiles of PWUD reporting opioid-related NFOD were seen over time. Notably, there was a sudden increase in reports of overdose following exposure to unknown substances since 2015, the majority of whom reported no recent addiction treatment engagement. Further study into patterns of substance use and strategies to improve addiction treatment engagement is needed to improve and focus overdose prevention efforts.

Slow release oral morphine versus methadone for opioid use disorder in the fentanyl era (pRESTO): Protocol for a non-inferiority randomized clinical trial

BACKGROUND

North America is facing an unprecedented public health crisis of opioid-related morbidity and mortality, increasingly as a result of the introduction of illicitly manufactured fentanyl into the street drug market. Although the treatment of opioid use disorder (OUD) is a key element in the response to the opioid overdose epidemic, currently available pharmacotherapies (e.g., methadone, buprenorphine) may not be acceptable to or effective in all patients. Available evidence suggests that slow-release oral morphine (SROM) has similar efficacy rates as methadone with respect to promoting abstinence, and with improvements in a number of patient-reported outcomes among persons using heroin. However, little is known about the relative effectiveness and acceptability of SROM compared to methadone in the context of fentanyl use. This study aims to address this research gap.

METHODS

pRESTO is a 24-week, open-label, two arm, non-inferiority, randomized controlled trial comparing SROM versus methadone for the treatment of OUD. Participants will be 298 clinically stable, non-pregnant adults with OUD, recruited from outpatient clinics in Vancouver, Canada, where the majority of the illicit opioids are contaminated with fentanyl. The primary outcome is suppression of illicit opioid use, measured by bi-weekly urine drug screens. Secondary outcomes include: treatment retention, medication safety, overdose events, treatment satisfaction, psychological functioning, changes in drug-related problems, changes in quality of life, opioid cravings, other substance use, and cost-effectiveness.

DISCUSSION

pRESTO will be among the first studies to evaluate treatment options for individuals primarily using synthetic street opioids, providing important evidence to guide treatment strategies for this population.

The impact of high-dose opioid prescription on mortality rates among people living with HIV: A retrospective cohort study

OBJECTIVES

High-dose opioid use is associated with increased morbidity, mortality, and healthcare utilization. People living with HIV (PLHIV) are frequently prescribed these medications to manage their pain. However, little is known about the relationship between being prescribed high doses of opioids (> 90 MME/d) and mortality risk among this population. The objective of this study was to examine the trends in mortality and the relationship between high-dose opioid analgesic prescribing and mortality among PLHIV.

METHODS

Utilizing the STOP HIV/AIDS cohort--a population-level linked database of treatment of PLHIV in British Columbia--we conducted bivariable and multivariable generalized estimating equation (GEE) models with a Poisson distribution to examine the relationship between high-dose opioid prescription and all-cause mortality rates in the study sample.

RESULTS

Between 1996 and 2015, 9272 PLHIV were included in the study. Age- and sex-adjusted mortality rate (using the 2011 Canadian population as the reference) was 30.99 per 1000 person-years (95% confidence interval [CI]: 28.11-33.88). In a multivariable GEE model with adjustment for various demographic and clinical confounders, there was a positive and independent association between being prescribed high-dose opioids and all-cause mortality rates (adjusted rate ratio [ARR] = 3.01; 95%CI: 2.47-3.66).

DISCUSSION

We found that mortality rates were significantly higher among PLHIV who were prescribed high-dose opioids compared to those who were prescribed lower doses. Our results highlight the risk associated with the prescribing of high-dose opioids to manage HIV-related pain and emphasize the need to explore non-opioid approaches to pain management.