Evaluation of the gap in delivery of opioid agonist therapy among individuals with opioid-related health problems: a population-based retrospective cohort study.

AIMS: Although opioid-related harms have reached new heights across North America, the size of the gap in opioid agonist therapy (OAT) delivery for opioid-related health problems is unknown in most jurisdictions. This study sought to characterize the gap in OAT treatment using a cascade of care framework, and determine factors associated with engagement and retention in treatment. DESIGN: A population-based retrospective cohort study. SETTING: Ontario, Canada. PARTICIPANTS: Individuals who sought medical care for opioid-related health problems or died from an opioid-related cause between 2005 and 2019. MEASUREMENTS: Monthly treatment status for buprenorphine/naloxone or methadone OAT between 2013 and 2019 (i.e. 'off OAT', 'retained on OAT < 6 months', 'retained on OAT ≥ 6 months'). FINDINGS: Of 122 811 individuals in the cohort, 97 516 (79.4%) received OAT at least once during the study period. There was decreasing 6-month treatment retention over time. Model results indicated that males had higher odds of being on OAT each month [odds ratio (OR) = 1.26, 95% confidence interval (CI) = 1.23-1.28] but lower odds of OAT retention (OR = 0.90, 95% CI = 0.88-0.92), while the reverse was observed for older individuals (monthly: OR = 0.76 per 10-year increase, 95% CI = 0.76-0.77; retention: OR = 1.36 per 10-year increase, 95% CI = 1.34-1.38) and individuals with higher neighbourhood income (e.g. highest income quintile, monthly: OR = 0.79, 95% CI = 0.77-0.82; highest income quintile, retention: OR = 1.15, 95% CI = 1.11-1.20). Individuals residing in rural areas and with a history of mental health diagnoses had poorer outcomes overall, including lower odds of being on OAT each month (rural: OR = 0.75, 95% CI = 0.73-0.78; mental health: OR = 0.89, 95% CI = 0.87-0.92) and OAT retention (rural: OR = 0.79, 95% CI = 0.77-0.82; mental health: OR = 0.81, 95% CI = 0.78-0.83), as well as higher risk of starting/stopping OAT [rural, starting OAT: hazard ratio (HR) = 1.07, 95% CI = 1.05-1.10; mental health, starting OAT: HR = 1.20, 95% CI: 1.18-1.23; rural, stopping OAT: HR = 1.24, 95% CI: = 1.22-1.26; mental health, stopping OAT: HR = 1.11, 95% CI = 1.09-1.13]. Individuals with a history of mental health diagnoses also had a higher risk of death, regardless of OAT status (off OAT death: HR = 1.49, 95% CI = 1.33-1.66; on OAT death: HR = 1.20, 95% CI = 1.09-1.31). CONCLUSIONS: Factors influencing engagement and declining retention in treatment with opioid agonist therapy in Ontario's health system include age, sex and neighbourhood income, as well as mental health diagnoses or residing in rural regions.

Exploring COVID-19 vaccine uptake, confidence and hesitancy among people experiencing homelessness in Toronto, Canada: protocol for the Ku-gaa-gii pimitizi-win qualitative study.

INTRODUCTION: People experiencing homelessness are at high risk for COVID-19 and poor outcomes if infected. Vaccination offers protection against serious illness, and people experiencing homelessness have been prioritised in the vaccine roll-out in Toronto, Canada. Yet, current COVID-19 vaccination rates among people experiencing homelessness are lower than the general population. This study aims to characterise reasons for COVID-19 vaccine uptake and hesitancy among people experiencing homelessness, to identify strategies to overcome hesitancy and provide public health decision-makers with information to improve vaccine confidence and uptake in this priority population. METHODS AND ANALYSIS: The Ku-gaa-gii pimitizi-win qualitative study (formerly the COVENANT study) will recruit up to 40 participants in Toronto who are identified as experiencing homelessness at the time of recruitment. Semistructured interviews with participants will explore general experiences during the COVID-19 pandemic (eg, loss of housing, social connectedness), perceptions of the COVID-19 vaccine, factors shaping vaccine uptake and strategies for supporting enablers, addressing challenges and building vaccine confidence. ETHICS AND DISSEMINATION: Approval for this study was granted by Unity Health Toronto Research Ethics Board. Findings will be communicated to groups organising vaccination efforts in shelters, community groups and the City of Toronto to construct more targeted interventions that address reasons for vaccine hesitancy among people experiencing homelessness. Key outputs will include a community report, academic publications, presentations at conferences and a Town Hall that will bring together people with lived expertise of homelessness, shelter staff, leading scholars, community experts and public health partners.