The effects of a provincial opioid prescribing standard on opioid prescribing for pain: interrupted series analysis

BackgroundIn 2016, the College of Physicians and Surgeons of British Columbia released a legally enforceable opioid prescribing practice standard for the treatment of chronic non-cancer pain (CNCP). The standard was revised in 2018, following physicians, patient groups and key partners concerns it was inappropriately interpreted. We tested the effects of the practice standard on access to opioids for people living with CNCP; and spillover effects on people living with cancer or receiving palliative care. MethodsWe used comprehensive administrative health data and multiple baseline interrupted time series analysis to evaluate the effects of the 2016 practice standard and 2018 revision. ResultsThe practice standard accelerated pre-existing declining trends in morphine milligram equivalents (MME) dispensed per person living with CNCP (-0.1%, 95% CI: -0.2, 0.0%), but also for people living with cancer (-0.7%, 95% CI: -1.0, -0.5%) or receiving palliative care (-0.3%, 95% CI: -0.5, 0.0%). Trends for the proportion of people with CNCP prescribed an opioid >90 MME daily dose (-0.3%, 95% CI: -0.4, 0.2%), co-prescribed benzodiazepine or other hypnotic (-0.6%, 95% CI: -0.7, -0.5%), and rapidly tapered (0.1%, 95% CI: -0.2, 0.0%) also declined more quickly. While level effects were generally in the same direction, the proportion of people rapidly tapered immediately post-implementation increased 2.0% (95% CI: 0.4, 3.3%). Trends slowed or reversed post-2018 revision. InterpretationThe 2016 practice standard was associated with an immediate and long-lasting effect on physicians opioid prescribing behaviours, including negative spillover effects on tapering, and for people living with cancer or receiving palliative care.