WiP Seminar: Bohdan Nosyk

Bohdan Nosyk, PhD, MA
Scientist, Advancing Health
Professor, Faculty of Health Sciences, Simon Fraser University
Adjunct Professor, Department of Statistics and Actuarial Sciences, Simon Fraser University

Comparing buprenorphine/naloxone and methadone for the treatment of opioid use disorder using population-level data

Importance: Previous comparative effectiveness studies between buprenorphine and methadone provided limited evidence on differences in treatment effects across key subgroups and drew from populations who use primarily heroin or prescription opioids, though fentanyl use is increasing across North America. 

Objectives: Assess the risk of treatment discontinuation and mortality among individuals receiving buprenorphine/naloxone versus methadone for opioid use disorder treatment.  

Design, Setting, and Participants: Population-based retrospective cohort study using linked health administrative databases in British Columbia, Canada including treatment recipients between 01/01/2010-03/17/2020 that were ≥18 years old and not incarcerated, pregnant or in palliative cancer care at initiation. 

Exposures: Receipt of buprenorphine/naloxone or methadone among incident (first-time) users and prevalent new users (including first and subsequent treatment attempts). 

Main Outcomes and Measures: Hazard ratios with 95% compatibility (“confidence”) intervals (CI) were estimated for treatment discontinuation (≥5 days for methadone, ≥6 days for buprenorphine/naloxone) and all-cause mortality within 24 months using discrete-time survival models for comparisons of medications as assigned at initiation regardless of treatment adherence (“initiator”) and received according to guidelines (per-protocol (PP) analysis). 

Results: 30,891 incident users were included in initiator analysis and 25,614 in PP analysis. Incident users of buprenorphine/naloxone had higher risk of treatment discontinuation compared to methadone in initiator analyses, with limited change in estimates at optimal dose in PP analysis. PP analyses on mortality during treatment exhibited ambiguous results among incident and prevalent users. Results were consistent after introduction of fentanyl, across patient subgroups and sensitivity analyses. 

Conclusions: Methadone was associated with lower risk of treatment discontinuation compared to buprenorphine/naloxone. Risk of mortality during treatment was – although the CI estimate for the hazard ratio was wide.

This is a hybrid event, you may attend in person or virtually. Please register and indicate your preference.