Effects of the new prescribing standards in British Columbia on consumption of opioids and benzodiazepines and z drugs.

OBJECTIVE: To evaluate the effects of the 2016 College of Physicians and Surgeons of British Columbia's (CPSBC's) opioid and benzodiazepine and z drug prescribing standards on the use of these medications in British Columbia.
DESIGN: Interrupted time-series analysis of community-prescribing records over a 30-month period: January 2015 to June 2017.
SETTING: British Columbia. PARTICIPANTS: Random sample of British Columbia residents with filled prescriptions during the study period. INTERVENTION: Introduction of CPSBC's opioid and benzodiazepine and z drug prescribing standards on June 1, 2016. MAIN OUTCOME MEASURES: Total weekly consumption of opioids (measured in morphine equivalents) and benzodiazepines and z drugs (measured in diazepam equivalents); and total monthly users of each class of medication.
RESULTS: Total consumption of both medication classes began to decline in late 2015, and the rate of decrease did not statistically significantly change following the implementation of the CPSBC standards in June 2016. In contrast, introduction of the standards was associated with an immediate 2% decrease in the number of monthly users of opioids for pain (P < .001), culminating in a 9% decrease over the course of the following year (P < .001). This trend was driven largely by a decrease in the number of continuing users; minimal change was seen in the number of new users during the study period. Trends in monthly users of benzodiazepines and z drugs mirrored those seen for opioids for pain.
CONCLUSION: Implementation of the 2016 CPSBC standards did not change a pre-existing downward trend in consumption of opioids or benzodiazepines and z drugs that began 6 months earlier. However, the standards did have a small effect on the number of monthly users of these medications, with a decrease in opioid prescribing among continuing users. Given the risk of destabilization of patients who are discontinued from opioid therapy, future research should assess how patient health outcomes are related to changing prescribing practices. Copyright© the College of Family Physicians of Canada.