Examining the association between fentanyl use and perceived adequacy of methadone dose: A retrospective cohort study.

Background: People exposed to fentanyl may report that the dose of methadone in the commonly accepted therapeutic range feels too low. We examined self-reported methadone dose adequacy.

Methods: We conducted a retrospective cohort study of individuals prescribed methadone at a dose of at least 60mg daily using data from three community-recruited prospective cohort studies of people who use drugs in Vancouver, Canada from December 2016 through March 2020.

The Impact of Longitudinal Substance Use Patterns on the Risk of Opioid Agonist Therapy Discontinuation: A Repeated Measures Latent Class Analysis.

Unlabelled: Polysubstance use is prevalent among individuals on opioid agonist treatment (OAT), yet past studies have focused primarily on distinct substances and their association with OAT retention. Data was collected from two prospective cohorts between 2005 and 2020 in Vancouver, Canada. Among 13,596 visits contributed by 1445 participants receiving OAT, we employed repeated measures latent class analysis using seven indicators and identified four longitudinal substance use classes.

Impacts of the COVID-19 pandemic on the availability and retail price of unregulated drugs in Vancouver, Canada: An interrupted time-series analysis, 2018-2022.

Background: Impacts of the COVID-19 pandemic on unregulated drug markets in North America have not been well characterized. We sought to estimate potential changes in the availability and retail price of unregulated drugs in Vancouver, Canada pre- vs. post-emergence of the COVID-19 pandemic.

Road to Recovery: protocol for a mixed-methods prospective cohort study evaluating the impact of a new model of substance use care in a Canadian setting.

Introduction: The Road to Recovery (R2R) Initiative is an innovative model of substance use care that seeks to increase treatment capacity by creating approximately 100 new addiction treatment beds to provide on-demand addiction care in Vancouver, British Columbia, for patients with substance use disorders. The new model also coordinates the region's existing clinical substance use services to support patients across a care continuum that includes traditional office-based addiction treatment and harm reduction services, early withdrawal management and more intensive abstinence-based treatment programming. To understand the impact of offering on-demand and coordinated substance use care, an observational cohort of individuals who access any R2R clinical service will be created to examine health and social outcomes over time.

Initiation and/or re-initiation of drug use among people who use drugs in Vancouver, Canada from 2021 to 2022: a prospective cohort study.

Objectives: Widespread health service disruptions resulting from the COVID-19 pandemic coincided with a dramatic increase in overdose deaths among people who use drugs (PWUD) in Vancouver, Canada. Those with a history of injection drug use are known to be at heightened risk of substance-associated harms. Drug use patterns and associated sociodemographic and health care utilization trends have been understudied in this population since the pandemic onset.

Preferred pharmaceutical-grade opioids to reduce the use of unregulated opioids: A cross-sectional analysis among people who use unregulated opioids in Vancouver, Canada.

Objectives: Many people who use drugs in the United States and Canada continue to access the contaminated unregulated drug supply, resulting in the ever-escalating overdose epidemic. In Canada, even in areas where healthcare providers are authorized to prescribe alternatives to the unregulated supply (e.g.

Involuntary discharge from drug or alcohol treatment programs in Vancouver, Canada.

Background: Retention in substance use treatment is essential to treatment success. While programmatic factors are known to influence retention, less is known about the role of involuntary discharges from drug or alcohol treatment programs. Therefore, we sought to identify the prevalence of and factors associated with involuntary discharge due to ongoing substance use.

Characterizing the Use of Healthcare Access Supports Among People Who Use Drugs in Vancouver, Canada, 2017 to 2020: A Cohort Study.

Background: For structurally marginalized populations, including people who use drugs (PWUD), equitable access to healthcare can be achieved through healthcare access supports. However, few studies characterized utilization of formal (eg, outreach workers, healthcare professionals) and informal (eg, friends/family) supports. Therefore, we sought to estimate the prevalence of and factors associated with receiving each type of support among PWUD.

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

Background: The COVID-19 pandemic had a disproportionate impact on the health and wellbeing of people who use drugs (PWUD) in Canada. However less is known about jurisdictional commonalities and differences in COVID-19 exposure and impacts of pandemic-related restrictions on competing health and social risks among PWUD living in large urban centres.

Methods: Between May 2020 and March 2021, leveraging infrastructure from ongoing cohorts of PWUD, we surveyed 1,025 participants from Vancouver (n = 640), Toronto (n = 158), and Montreal (n = 227), Canada to describe the impacts of pandemic-related restrictions on basic, health, and harm reduction needs.

Receipt of COVID-19 emergency funds and engagement in sex work during COVID-19 among people who use drugs: evidence from Vancouver, Canada.

Background: During the early period of the COVID-19 pandemic, public health orders disrupted income generation in numerous sectors and many governments provided emergency financial support. Access to government support and changes in engagement in sex work during the early period of the pandemic among people who use drugs (PWUD) are not well described. In the present study, we investigate the prevalence and correlates of engaging in sex work during the COVID-19 pandemic, among PWUD in Vancouver, Canada.

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.

Denial of prescription pain medication among people who use drugs in Vancouver, Canada.

Background: People who use drugs experience pain at two to three times the rate of the general population and yet continue to face substantial barriers to accessing appropriate and adequate treatment for pain. In light of the overdose crisis and revised opioid prescribing guidelines, we sought to identify factors associated with being denied pain medication and longitudinally investigate denial rates among people who use drugs.

Methods: We used multivariable generalized estimating equations analyses to investigate factors associated with being denied pain medication among people who use drugs reporting pain in three prospective cohort studies in Vancouver, Canada.

Patterns of Socioeconomic Marginalization among People Who Use Drugs: A Gender-Stratified Repeated Measures Latent Class Analysis.

Socioeconomic factors are important correlates of drug use behaviors and health-related outcomes in people who use drugs (PWUD) residing in urban areas. However, less is known about the complex overlapping nature of socioeconomic conditions and their association with a range of individual, drug use, and health-related factors in men and women who use drugs. Data were obtained from two community-recruited prospective cohorts of PWUD.

Evaluating the agreement between different substance use recall periods in multiple HIV cohorts.

Background: This study aims to evaluate the agreement in substance use on both binary and ordinal scales between 3-month and 6-month recall periods with samples from different communities, demographic backgrounds, and HIV status.

Methods: We administered the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) to 799 participants from three different North American cohorts focused on substance use and HIV. We conducted a within-person agreement analysis by calculating the agreement levels and Kappa statistic between data collected using the 3-month recall ASSIST and 6-month custom substance use surveys as well as different terminology for each substance in multiple cohorts.

Uptake of SARS-CoV-2 vaccination among structurally-marginalized people who use drugs in Vancouver, Canada.

We sought to evaluate the rates and predictors of SARS-CoV-2 vaccination among members of a structurally-marginalized population of people who use drugs (PWUD) during a targeted, community-wide, vaccination campaign in Vancouver, Canada. Interviewer-administered data were collected from study participants between June 2021 and March 2022. Generalized estimating equation analysis was used to identify factors associated with SARS-CoV-2 vaccine uptake, ascertained through a province-wide vaccine registry.

Cannabis use to manage stimulant cravings among people who use unregulated drugs.

Background: We sought to analyze the association between cannabis use to manage stimulant cravings and self-reported changes in stimulant use among structurally marginalized people who use unregulated drugs (PWUD).

Methods: The data for this secondary analysis was collected from a cross-sectional questionnaire administered to people who concurrently use cannabis and unregulated stimulants in Vancouver, Canada. We used logistic regression models to analyze the association between cannabis use to manage stimulant cravings and self-reported changes in the frequency of stimulant use.

Police seizure of drugs without arrest among people who use drugs in Vancouver, Canada, before provincial 'decriminalization' of simple possession: a cohort study.

Background: Several jurisdictions in Canada have recently considered decriminalizing possession of illicit drugs for personal use (henceforth, simple possession) as part of their responses to the ongoing drug toxicity/overdose crisis. In this context, we sought to examine an early implementation case of a de facto depenalization policy of simple possession offences in Vancouver, Canada, that was enacted in 2006. Specifically, we characterized experiences of people who use drugs (PWUD) whose drugs were discretionally seized by police without arrest.

Cannabis use to manage opioid cravings among people who use unregulated opioids during a drug toxicity crisis.

Background: Accumulating evidence has indicated that cannabis substitution is often used as a harm reduction strategy among people who use unregulated opioids (PWUO) and people living with chronic pain. We sought to investigate the association between cannabis use to manage opioid cravings and self-reported changes in opioid use among structurally marginalized PWUO.

Methods: The data were collected from a cross-sectional questionnaire administered to PWUO in Vancouver, Canada.

Socioeconomic marginalization and risk of overdose in a community-recruited cohort of people who use drugs: A longitudinal analysis.

Background: Poverty and socioeconomic disadvantage are important contributors to drug-related harm, but their precise role in overdose risk remains poorly understood. We sought to examine linkages between socioeconomic marginalization and non-fatal overdose risk in a community deeply affected by the ongoing drug poisoning crisis.

Methods: This observational study used data derived from two community-recruited prospective cohorts of people who use drugs (PWUD) in Vancouver, British Columbia, Canada.

First-line opioid agonist treatment as prevention against assisting others in initiating injection drug use: A longitudinal cohort study of people who inject drugs in Vancouver, Canada.

Background: Among people who inject drugs, frequent injecting and experiencing withdrawal are associated with facilitating others' first injections. As these factors may reflect an underlying substance use disorder, we investigated whether first-line oral opioid agonist treatment (OAT; methadone or buprenorphine/naloxone) reduces the likelihood that people who inject drugs help others initiate injecting.

Methods: We used questionnaire data from semi-annual visits between December 2014-May 2018 on 334 people who inject drugs with frequent non-medical opioid use in Vancouver, Canada.

Cannabidiol as a Harm Reduction Strategy for People Who Use Drugs: A Rapid Review.

Objective: The drug poisoning crisis throughout North America necessitates novel harm reduction approaches. Emerging evidence suggests that cannabidiol (CBD) may have some utility as a harm reduction modality for those with problematic substance use. This rapid review aimed to synthesize available evidence on CBD as a potential harm reduction tool for people who use drugs while providing clinical and research insights.

Food insecurity during the COVID-19 pandemic who use drugs in Vancouver, Canada.

Objective: To examine prevalence and factors associated with food insecurity among people who use drugs (PWUD) during the first year of the COVID-19 pandemic and the overdose crisis.

Design: This cross-sectional study employs multivariable logistic regression to identify factors associated with self-reported food insecurity.

Participants: PWUD who are part of three community-recruited cohorts.

Latent polydrug use patterns and the provision of injection initiation assistance among people who inject drugs in three North American settings.

Introduction: We sought to identify latent profiles of polysubstance use patterns among people who inject drugs in three distinct North American settings, and then determine whether profile membership was associated with providing injection initiation assistance to injection-naïve persons.

Methods: Cross-sectional data from three linked cohorts in Vancouver, Canada; Tijuana, Mexico; and San Diego, USA were used to conduct separate latent profile analyses based on recent (i.e.