Effect of the Comprehensive Addiction and Recovery Act (CARA) on Buprenorphine Prescribing for Opioid Use Disorder Among Medicare Beneficiaries With Back Pain.

Abstract

Observational cohort study. To examine the effects of the Comprehensive Addiction and Recovery Act (CARA) on buprenorphine prescribing and opioid use disorder (OUD) among Medicare beneficiaries with back pain. Enacted in January 2017, CARA extended buprenorphine prescribing authority to Nurse Practitioners (NP) and Physician Assistants (PA) to treat OUD, defined as a physical or psychological dependence on opioids, but adoption varied by state. Leveraging this policy variation, we examined the effect of CARA on buprenorphine prescribing and OUD employing Medicare beneficiaries over age 65 with back pain from 2016 to 2019, and who were eligible for Part D prescription drug benefits. Only buprenorphine and buprenorphine/naloxone combinations that are FDA-approved for OUD treatment were included as our outcome. A difference-in-difference regression examined the change in buprenorphine prescribing and OUD before and after CARA between states that did and did not expand prescription authority. Subgroup analysis examined treatment effect heterogeneity by sex and race/ethnicity. States that adopted a full scope-of-practice under CARA had a significant increase in buprenorphine prescribing (6.5%, 95% CI: 1.3%, 12.2%) and a reduction in OUD (7.2%, 95% CI: -9.3%, -4.8%) compared with states that did not expand prescribing authority after the policy implementation. States that expanded prescribing authority following CARA had a disproportionate increase in use of buprenorphine and a reduction in OUD among males and Hispanic patients compared with female and White patients. The magnitude of the policy effects increased over time across all groups. CARA was associated with increased buprenorphine prescribing and a reduction in OUD among older adults with back pain. Expanded authorization of prescription of buprenorphine to treat OUD by NPs/PAs in states that have not adopted full scope-of-practice under CARA might effectively reduce OUD, as well as racial/ethnic disparities in buprenorphine prescribing and OUD. Level 3.