Kora DeBeck’s research while affiliated with Government of British Columbia, Canada and other places

Introduction Amidst the opioid overdose crisis, there is interest in cannabis use for pain management and harm reduction. We investigated the relationship between cannabis use and cessation of unregulated opioid use among people who use drugs (PWUD) living with chronic pain. Method Data for analyses were collected from three prospective cohort studies in Vancouver, Canada. All cohort participants who completed at least two study visits and reported both pain and unregulated opioid use in the past 6 months were included in the present study. We analysed the association between cannabis use frequency and opioid cessation rates using extended Cox regression models with time‐updated covariates. Results Between June 2014 and May 2022, 2340 PWUD were initially recruited and of those 1242 PWUD reported chronic pain, use of unregulated opioids and completed at least two follow‐up visits. Of these 1242 participants, 764 experienced a cessation event over 1038.2 person‐years resulting in a cessation rate of 28.5 per 100 person‐years (95% confidence interval [CI] 25.4–31.9). Daily cannabis use was positively associated with opioid cessation (adjusted hazard ratio 1.40, 95% CI 1.08–1.81; p = 0.011). In the sex‐stratified sub‐analyses, daily cannabis use was significantly associated with increased rates of opioid cessation among males (adjusted hazard ratio 1.50, 95% CI 1.09–2.08; p = 0.014). Discussion and Conclusions Participants reporting daily cannabis use exhibited higher rates of cessation compared to less frequent users or non‐users. Observed sex‐specific differences in cannabis use and opioid cessation suggest potential differences in cannabis use behaviours and effects. Our findings add to the growing evidence supporting the potential benefits of cannabis use among PWUD, underlining the need for further research.

Objective Using an innovative data sharing model, we assessed the impacts of the COVID-19 pandemic on the health of people who inject drugs (PWID). Design The PWID Data Collaborative was established in 2021 to promote data sharing across PWID studies in North America. Contributing studies submitted aggregate data on 23 standardized indicators during four time periods: pre-pandemic (Mar 2019 – Feb 2020), early-pandemic (Mar 2020 – Feb 2021), mid-pandemic (Mar 2021 - Feb 2022), and late pandemic (Mar 2022 - Feb 2023). Methods We present study-specific and meta-analyzed estimates for the percentage of PWID who took medications for opioid use disorder, received substance use treatment, shared syringes or injection equipment, had a mental health condition, had been incarcerated, or had experienced houselessness. To examine change over time across indicators, we fit a random effects meta-regression model to prevalence estimates using time as a moderator. Results Thirteen studies contributed estimates to the Data Collaborative on these indicators, representing 6,213 PWID interviews. We observed minimal change across prevalence of the six indicators between the pre-pandemic (March 2019 – February 2020) and three subsequent time periods, overall or within individual studies. Considerable heterogeneity was observed across study- and time-specific estimates. Conclusions Limited pandemic-related change observed in indicators of PWID health is likely a result of policy and supportive service-related changes and may also reflect resilience among service providers and PWID themselves. The Data Collaborative is an unprecedented data sharing model with potential to greatly improve the quality and timeliness of data on the health of PWID.

Background: Epigenome studies of human HIV-1 (HIV) in whole blood have uncovered a growing list of differentially methylated genes associated with either HIV acquisition, disease progression, or both. Cocaine use is associated with increased disease severity, and methylation changes in some of the HIV-associated genes mediate this effect. Many of these genes are critical players in innate immune response, including both regulators and targets of interferon-alpha and NF-kB activation. However, no study to date has evaluated the gene expression dynamics for these genes in the context of HIV. Methods: Targeted gene expression analyses were performed on 588 people who used illicit drugs within a harmonized cohort comprised of the Vancouver People Who Inject Drugs Study (VPWIDS) using RNAseq in whole blood, including 227 people living with HIV (PLWH). Eighteen genes were selected from six recent epigenome-wide association studies to test for differential expression by HIV status. Both gene-level and transcript-level expression changes were estimated using negative binomial regression models. Results: Nine of the 18 target genes exhibited significant upregulation in PLWH after multiple hypothesis testing correction: EPSTI1, IFI44L, IFIT3, MX1, NLRC5, PARP9, PLSCR1, RIN2, and RSAD2. Transcript-level analysis detected additional upregulation of isoforms for genes CD44, RASSF3, and TAP1. Stratified analysis by cocaine use revealed MX1 and RSAD2 to be exclusively upregulated among PLWH who recently used cocaine. Pathway analysis identified significant dysregulation in the interferon alpha/beta signaling pathway. Conclusions: We confirm the dysregulation of genes previously reported to have differential methylation among PLWH. Results from this study support the model of epigenetic changes altering gene expression for key immune genes such as NLRC5 and MX1, and demonstrate systemic dysregulation of genes involved in innate immune function.

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. Methods and analysis This prospective mixed-methods study will invite individuals from Vancouver, Canada, who access substance use treatment through the R2R model of care to (1) complete a baseline and 12-month follow-up quantitative questionnaire that solicits sociodemographic, substance use and previous addiction treatment data and (2) provide consent to the use of participants’ personal identifiers to access health records for chart review and for annual linkage to select health and administrative databases to allow for ongoing (virtual) community follow-up over 5 years. Additionally, a purposive sample of cohort participants will be invited to participate in baseline and 12-month follow-up qualitative interviews to share their experiences accessing R2R and identify challenges and opportunities associated with the implementation of R2R. Ethics and dissemination The study was approved by the University of British Columbia Providence Health Care Research Ethics Board in September 2023. Results from the proposed study will be published in peer-reviewed journals, presented at national and international scientific conferences and disseminated through regular meetings with policymakers, individuals with lived and living experience, and other high-level stakeholders, academic presentations and lay media.

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. We sought to understand patterns of drug use initiation and/or re-initiation among people with a history of injection drug use (IVDU). Methods Data were obtained from three harmonized prospective cohort studies of PWUD in Vancouver. Participants with a lifetime history of IVDU who responded to a survey between June 2021 and May 2022 were included. The primary outcome variable was a composite of substance use initiation and re-initiation over the study period, labelled as drug (re)-initiation. A multivariable generalized linear mixed-effects model was used to examine factors associated with self-reported (re)-initiation of substance use over the past six months. Results Among 1061 participants, the median age was 47 years at baseline and 589 (55.5%) identified as men. In total, 183 (17.2%) participants reported initiating and/or re-initiating a drug, with 44 (4.1%) reporting new drug initiation and 148 (14.0%) reporting drug re-initiation (9 participants responded ‘yes’ to both). Overall, unregulated stimulants (e.g., crystal methamphetamine and cocaine) were the most common drug class (re-)initiated (n = 101; 55.2%), followed by opioids (n = 74; 40.4%) and psychedelics (n = 36; 19.7%). In the multivariable analysis, (re-)initiation of drug use was independently associated with recent IVDU (adjusted odds ratio [AOR] 2.62, 95% confidence interval [CI] 1.02, 6.76), incarceration (AOR 3.36, CI 1.12, 10.14) and inability to access addiction treatment (AOR 4.91, 95% CI 1.22, 19.75). Conclusions In an era impacted by the intersecting effects of the COVID-19 pandemic and the overdose crisis, nearly one in five PWUD with a history of IVDU began using a new drug and/or re-started use of a previous drug. Those who reported drug (re-)initiation exhibited riskier substance use behaviours and reported difficulty accessing treatment services. Our findings underscore the need to provide additional resources to support this high-risk population.