Impact of a Long-Term Benzodiazepine Use Prior Authorization Policy on Utilization and Non-Fatal Adverse Health Outcomes in a State Medicaid Program.

BACKGROUND

Despite limited evidence of efficacy and well-established risks, long-term benzodiazepine use remains common. In July 2016, the Oregon Medicaid program introduced a prior authorization policy limiting benzodiazepine prescriptions to 4 weeks.

OBJECTIVES

To evaluate the impact of Oregon's benzodiazepine policy on medication utilization and health outcomes.

RESEARCH

DESIGN

Interrupted time series regressions from January 2015-December 2017 (18 mo pre vs. post-policy).

SUBJECTS: Rolling cohorts of adult benzodiazepine recipients with 6 months of continuous enrollment before and after each month of observation.

MEASURES: Benzodiazepine utilization included monthly measures of overall, prevalent long-term, and incident long-term medication use. Harms included a composite measure of emergency department or inpatient admissions for overdose, self-harm, acute withdrawal, or acute psychiatric events, and were compared with patients using similar medications that were not affected by the policy.

RESULTS

The study population included 69,143 benzodiazepine recipients; 68% were female, and the average age was 41 years or older. Following policy implementation, there was a significant segment decrease (-​​​29.82 recipients/1000 patients; 95% CI: -​​​33.75 to -​​​25.89) in incident long-term benzodiazepine use and a 1.17 recipients/1000 patients/month (95% CI: 0.82-1.52) increase in trend. Trends in prevalent long-term (-1.16 recipients/1000 patients/month: 95% CI: -1.32 to -0.99) benzodiazepine use also declined. Modest trend decreases in harm were observed among all cohorts.

CONCLUSIONS

A policy to limit benzodiazepine duration was associated with a substantial reduction in progression to longer-term use and modest declines in the trend for potential harms.