Buprenorphine treatment episode duration, dosage, and concurrent prescribing of benzodiazepines and opioid analgesics: The effects of Medicaid prior authorization policies

Background: Buprenorphine is an effective medication for the treatment of opioid use disorder (OUD), but the association between prior authorization policies and quality of care for individuals receiving buprenorphine treatment is not well-understood. Methods: Using 2006–2013 Medicaid Analytic eXtract (MAX) data from 34 states and the District of Columbia, we identified 294,031 episodes of buprenorphine treatment for OUD among individuals aged 14–64 years. We estimated generalized difference-in-differences models to examine the association between buprenorphine prior authorization policies and changes in buprenorphine treatment quality along four dimensions: (1) duration of at least 180 days, (2) dosage of at least 8 milligrams, and concurrent prescribing of (3) opioid analgesics and (4) benzodiazepines. Results: Buprenorphine prior authorization policies were associated with an 11-percentage point reduction (p < 0.01) in the likelihood of episodes with a duration of at least 180 days in the first four years after policy implementation. The policy was not associated with changes in effective dosage or concurrent prescribing of opioid analgesics or benzodiazepines. Conclusions: Buprenorphine prior authorization policies were associated with a sizeable and significant reduction in episodes of at least 180 days duration, underscoring the importance of identifying and removing barriers to effective and appropriate OUD care.