Estimates of opioid use disorder prevalence from a regression-based multi-sample stratified capture-recapture analysis.

Background: An epidemic of opioid overdose has spread across North America, with illicit drug-related overdose emerging as a leading cause of death in recent years. Estimates of opioid use disorder (OUD) prevalence at the level of the public health service delivery area are needed to project resource needs and identify priority areas for targeted intervention. Our objective is to estimate the annual prevalence of OUD in British Columbia (BC), Canada, from 2000 to 2017.

Methods: We performed a multi-sample stratified capture-recapture analysis to estimate OUD prevalence in BC. The analysis included individuals identified from 3 administrative databases for 2000-2011 and 4 databases for 2012-2017, linked at the individual level. Negative binomial regression models on the counts of individuals within these strata were used to estimate prevalence, adjusting for dependency between databases.

Results: OUD prevalence in BC among people aged 12 years or older was 1.00 % (N = 34,663 individuals) in 2000 and increased to 1.54 % (N = 61,080) in 2011. Between 2013 and 2017 prevalence increased from 1.57 % (95 % confidence interval: 1.56-1.58) to 1.92 % (1.89-1.95; N = 83,760; 82,492-84,855). The greatest increases in prevalence were observed among males 12-30 years old and 31-44 years old, with 43.2 % and 40.2 % increases from 2013 to 2017.

Conclusions: In BC, the OUD prevalence was 1.92 % among people 12 years or older in 2017. We estimated that prevalence has nearly doubled since 2000, with the highest increases in prevalence observed among males under 45.