Impact of state opioid laws on prescribing in trauma patients.

Background: Excessive opioid prescribing has resulted in opioid diversion and misuse. In July 2018, Michigan's Public Act 251 established a state-wide policy limiting opioid prescriptions for acute pain to a 7-day supply. Traumatic injury increases the risk for new persistent opioid use, yet the impact of prescribing policy in trauma patients remains unknown. To determine the relationship between policy enactment and prescribing in trauma patients, we compared oral morphine equivalents prescribed at discharge before and after implementation of Public Act 251.

Methods: In this cross-sectional study, adult patients who received any oral opioids at discharge from a Level 1 trauma center between January 1, 2016, and June 30, 2021, were identified. The exposure was patients admitted starting July 1, 2018. Inpatient oral morphine equivalents per day 48 hours before discharge and discharge prescription oral morphine equivalents per day were calculated. Student's t test and an interrupted time series analysis were performed to compare mean oral morphine equivalents per day pre- and post-policy. Multivariable risk adjustment accounted for patient/injury factors and inpatient oral morphine equivalent use.

Results: A total of 3,748 patients were included in the study (pre-policy n = 1,685; post-policy n = 2,063). Implementation of the prescribing policy was associated with a significant decrease in mean discharge oral morphine equivalents per day (34.8 ± 49.5 vs 16.7 ± 32.3, P < .001). After risk adjustment, post-policy discharge prescriptions differed by -19.2 oral morphine equivalents per day (95% CI -21.7 to -16.8, P < .001). The proportion of patients obtaining a refill prescription 30 days post-discharge did not increase after implementation (0.38 ± 0.48 vs 0.37 ± 0.48, P = .7).

Conclusion: Discharge prescription amounts for opioids in trauma patients decreased by approximately one-half after the implementation of opioid prescribing policies, and there was no compensatory increase in subsequent refill prescriptions. Future work is needed to evaluate the effect of these policies on the adequacy of pain management and functional recovery after injury.