International Trends in Opioid Prescribing by Age and Sex from 2001 to 2019: An Observational Study Using Population-Based Databases from 18 Countries and One Special Administrative Region

Objective: To characterize multinational trends and patterns of opioid analgesic prescribing by sex and age. Design, Setting, and Participants: We studied opioid analgesic prescribing from 2001 to 2019 with common protocol using population-based databases from eighteen countries and one special administrative region. Main Outcome Measures: We measured opioid prescribing by geographical region, sex and age, estimating annual prevalent, incident, and nonincident opioid prescribing per 100 population with a 95% confidence interval (CI) and meta-analyzed the multinational and regional opioid prescribing with a random-effects model. Time trends were reported through average annual absolute changes, estimated using linear mixed models. We further explored the effect of sex and age on prevalent opioid prescribing in the multivariable analysis. Results: Over 248 million individuals were included. Pooled multinational opioid prescribing prevalence was 9.0% amongst included countries/regions. Opioid prescribing prevalence in 2015 ranged from 2.7% in Japan to 19.7% in Iceland. Average annual absolute changes in opioid prescribing prevalence per year ranged from − 1.53% (95% CI − 2.06, − 1.00; United States Medicaid) to + 1.24% (95% CI 1.02, 1.46; South Korea). Pooled multinational incident opioid prescribing (4.9%; 95% CI 4.1, 5.9) was higher than pooled multinational nonincident opioid prescribing (3.7%; 95% CI 2.9, 4.8). The female sex and older age were associated with higher opioid prescribing. Main limitations of this study include the absence of data from study duration or individuals not covered by the data sources and the lack of information on medication adherence and indication. Conclusions: Opioid prescribing remains unbalanced across geographical regions; however, results suggest a tendency to convergence across countries/regions. Differences in opioid prescribing by sex and age were identified.