(B-060) Opioid Agonist Treatment Dispensing Trends Between 2018 and 2022 Across Six Canadian Provinces

Background: Opioid agonist treatment (OAT) is recommended first-line for individuals with opioid use disorder (OUD). The prescribing guidance for OATs and the availability of different products has rapidly evolved in recent years. However, information on regional variations in OAT prescribing is required to inform policy and programming decisions on access to treatment for opioid use disorder in Canada.

Objectives: We examined OAT dispensing patterns across six Canadian provinces between 2018 and 2022.

Methods: We conducted a population-based repeated cross-sectional study of OAT recipients (i.e., methadone and buprenorphine-containing products) between January 2018 and December 2022, across six provinces (British Columbia, Alberta, Saskatchewan, Manitoba, Québec, and Ontario) using pharmacy dispensing records, regardless of payer (apart from Québec, where only claims insured by Quebec’s public drug insurance plan were available). We calculated population-adjusted rates of prevalent and incident OAT recipients as our primary and secondary outcome, respectively. We reported trends in monthly rates stratified by province and annual rates for each province stratified by age, sex, neighbourhood income quintile, location of residence, and OAT type.

Results: We observed varying prevalence of OAT use across provinces and over time, ranging from 1.38 to 5.29 per 1,000 in Quebec and British Columbia, respectively in 2022. Growth in annual prevalence rates was observed in Alberta (3.00 to 3.75 per 1,000) and Manitoba (1.68 to 2.39 per 1,000) between 2018 and 2022. Prevalence rates remained relatively stable in other provinces apart from a slight decline noted in 2022 in British Columbia, Ontario and Saskatchewan. OAT use was concentrated among people aged 25-44, males, and residents of lower income quintile neighbourhoods. In Ontario, Saskatchewan, and British Columbia, 1 in 100 individuals aged 25-44 were dispensed OAT in 2022. A shift towards buprenorphine prescribing occurred across all provinces, with 45% to 74% of OAT recipients prescribed a buprenorphine-containing product in 2022. Aforementioned patterns were generally consistent with incident OAT rates.

Conclusions: Cross-provincial differences in OAT rates may denote different underlying rates of opioid use disorder and access to treatment. The shift towards buprenorphine use should be considered carefully due to emerging evidence for improved treatment retention among methadone recipients in the context of Canada’s fentanyl dominated unregulated drug supply.