Dental Opioid Prescription Characteristics and the Risk of New, Persistent Use

INTRODUCTION: Dentists are a common source of opioid exposure. This study investigates the association between initial dental opioid prescription characteristics and subsequent persistent use and examines the rate of opioid overdose after initiation. METHODS: A retrospective cohort study was conducted among Ontario residents who were dispensed an initial opioid prescription originating from a dentist between October 2014 and September 2018 (data were analyzed in October 2019-May 2020). Exposures were characterized on the basis of the average daily dose in milligram morphine equivalents and the duration and formulation (long versus short acting) of the initial prescription. New, persistent use was defined as ≥1 opioid prescription within 90 days and another within 91-365 days after the initial prescription. The rate of an opioid overdose within 90 days after initiation was examined. RESULTS: Among 786,125 Ontarians who initiated a dentist-prescribed opioid, 34,880 (4.4%) developed persistent use, whereas 140 (0.72 per 1,000 person-years) had evidence of an overdose within 90 days. People dispensed an initial daily dose >90 milligram morphine equivalents (n=5,644, 0.7%) had significantly greater odds of persistence (AOR=1.20, 95% CI=1.07, 1.34) than those dispensed ≤20 milligram morphine equivalents (n=179,884, 22.9%). Persistence was also significantly associated with receiving longer prescription durations and a long-acting opioid on initiation. CONCLUSIONS: Among people who initiated a dentist-prescribed opioid, 1 in 23 experienced persistent use, and persistence was associated with the characteristics of the prescription. Prescribing lower doses, prescribing for shorter durations, and avoiding long-acting formulations may be an opportunity to lessen the risk of persistent opioid use.