Impact of baseline methamphetamine/amphetamine use on discontinuation of methadone and buprenorphine/naloxone among people with prescription-type opioid use disorder in Canada.

BACKGROUND AND OBJECTIVES: Although concurrent stimulant use is common among people with opioid use disorder (OUD), there is little evidence on its impacts on opioid agonist therapy (OAT) outcomes. This study sought to determine the impact of baseline methamphetamine/amphetamine use on discontinuation of OAT among individuals with prescription-type OUD (POUD) initiating methadone or buprenorphine/naloxone as part of a pragmatic randomized trial in Canada. METHODS: Secondary analysis of a pan-Canadian pragmatic trial conducted between 2017 and 2020 comparing supervised methadone versus flexible take-home dosing buprenorphine/naloxone models of care. Cox proportional hazard models were used to evaluate the effect of baseline methamphetamine/amphetamine use (measured by urine drug test [UDT]) on two discontinuation outcomes (i.e., assigned OAT discontinuation, any OAT discontinuation). RESULTS: Two hundred nine (n = 209) participants initiated OAT, of which 96 (45.9%) had positive baseline methamphetamine/amphetamine UDT. Baseline methamphetamine/amphetamine use was associated with shorter median times in assigned OAT (21 vs. 168 days, hazard ratio [aHR] = 2.45, 95% confidence interval [CI] = 1.60-3.76) and any OAT (25 days vs. 168 days, aHR = 2.06, CI = 1.32-3.24). No interaction between methamphetamine/amphetamine and assigned OAT was observed for either outcome (p > .05). CONCLUSION AND SCIENTIFIC SIGNIFICANCE: This study offers novel insights on the impact of methamphetamine/amphetamine use on OAT outcomes among people with POUD. Methamphetamine/amphetamine use was common and was associated with increased risk of OAT discontinuation. Supplementary interventions, including treatment for stimulant use, are needed to improve retention in OAT and optimize treatment outcomes in this population.

Characterising methamphetamine/amphetamine use among opioid agonist therapy-seeking adults with prescription-type opioid use disorder in Canada.

INTRODUCTION: There has been a significant increase in methamphetamine/amphetamine use in North America, particularly among people who use opioids. Despite its association with several negative health consequences, the population of people who use methamphetamine/amphetamine with opioids is not well characterised. The aim of this study was to investigate correlates of methamphetamine/amphetamine use among adults with prescription-type opioid use disorder (POUD) starting methadone or buprenorphine/naloxone as part of a pragmatic randomised treatment trial in Canada. METHODS: Multivariable logistic regression analyses were used to determine factors associated with baseline methamphetamine/amphetamine use (measured by urine drug test [UDT]) among participants of a pan-Canadian pragmatic trial conducted between 2017 and 2020 comparing supervised methadone versus flexible take-home dosing buprenorphine/naloxone models of care in people with POUD (e.g., licit or illicit, including fentanyl, prescribed or not). RESULTS: The sample included 269 participants, of which 142 (52.8%) had positive baseline methamphetamine/amphetamine UDT. In the multivariable model, positive fentanyl UDT (adjusted odds ratio [AOR] 13.21, 95% confidence interval [CI] 6.45, 28.30), non-fatal overdose in the last 6 months (AOR 2.26, CI 1.01, 5.17) and a lifetime history of opioid agonist therapy exposure prior to study entry (AOR 2.30, CI 1.09, 4.87) remained positively associated with baseline methamphetamine/amphetamine use. DISCUSSION AND CONCLUSIONS: In this sample of people with POUD, methamphetamine/amphetamine use was associated with markers of complex and severe OUD, including overdose risk. This suggests the need for targeted interventions to optimise treatment outcomes and prevent future overdoses in this population. CLINICAL TRIAL REGISTRATION: Available at: ClinicalTrials.gov NCT03033732.

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.

Feasibility and acceptability of collecting umbilical cord tissue for prenatal cannabis research: A mixed-methods research study.

BACKGROUND: Large-scale longitudinal studies with biological samples are needed to examine the associations between prenatal cannabis use and birth and developmental outcomes. OBJECTIVES: The aim of this study was to understand the feasibility and acceptability of collecting umbilical cord tissue for the purpose of cannabis use testing in a community sample. DESIGN: This is a mixed methods research study consisted of a prospective cohort study and a qualitative descriptive study. METHODS: This study was conducted in Vancouver, British Columbia between January 2021 and August 2022. Participants were recruited during pregnancy, and the umbilical cord tissues were collected at birth and tested for the presence of cannabinoids. After the completion of the study, participants completed an online open-ended questionnaire about their overall experience. Data were analyzed using descriptive and thematic analyses. RESULTS: Among the 85 eligible individuals, 57 people (67%) consented to the study. The cord tissue was collected for 39 participants (68.4%). The collection rates for participants with vaginal, elective, and emergency cesarean delivery were 73.0%, 71.4%, and 53.8%, respectively, and for those with spontaneous and induced labor were 81.5% and 50%, respectively. Four (7.0%) and seven participants (12.3%) reported prenatal cannabis use in direct and probing self-report questions, respectively. The agreement between any self-report and cord tissue test was moderate (kappa 0.53, 95% confidence interval 0.06-0.99). Qualitative findings were classified into five themes. CONCLUSION: The collection of cord tissue was perceived acceptable by most participants. Implementation of collection protocols for complex labors, a central hospital unit to liaise direct communications and active participants' involvement might increase the feasibility of future studies.

The Oral and Fecal Microbiota in a Canadian Cohort of Alzheimer's Disease.

BACKGROUND: Despite decades of research, our understanding of Alzheimer's disease (AD) etiology remains incomplete. In recent years, appreciation has grown for potential roles for the microbiota in shaping neurological health. OBJECTIVE: This study aimed to examine associations between the microbiota and AD in a human cross-sectional cohort. METHODS: Forty-five AD patients and 54 matched controls were recruited in Vancouver, Canada. Fecal and oral samples underwent 16S microbiota sequencing. A wide array of demographic and clinical data were collected. Differences between participant groups were assessed, and associations between microbes and clinical variables were examined within the AD population. RESULTS: The gut microbiota of AD patients displayed lower diversity relative to controls, although taxonomic differences were sparse. In contrast, the AD oral microbiota displayed higher diversity, with several taxonomic differences relative to controls, including a lower abundance of the families Streptococcaceae and Actinomycetaceae, and a higher abundance of Weeksellaceae, among others. The periodontitis-associated oral microbe Porphyromonas gingivalis was 5 times more prevalent among patients. No significant associations between gut or oral microbes and cognition were detected, but several correlations existed between microbes and mood disorders and BMI among patients, including a strong positive correlation between Alphaproteobacteria and depression score. CONCLUSION: The gut microbiota of AD patients was not overtly different from controls, although it displayed lower diversity, an overall marker of microbiota health. The oral microbiota did display marked differences. Cognition was not associated with a microbial signature, but other relevant AD factors including mood and BMI did demonstrate an association.