How Did Medicaid's 1115 Substance Use Disorder Waivers Increase Medication Treatment for Opioid Use Disorder?...

Policy Points States can use substance use disorder waivers to improve their program, but findings regarding the effects of these waivers on opioid use disorder medication treatment have shown mixed results. This study used a mixed-methods design to identify strategies that states undertook as part of their waiver and that may have led to increases in the use of methadone or buprenorphine. For methadone, adding coverage, increasing reimbursement rates, and engaging providers and managed care organizations may be effective strategies to increase the use of this medication. In contrast, no consistent strategies were identified for buprenorphine.

Starting in 2015, states could apply for section 1115 substance use disorder (SUD) waivers to strengthen their continuum of care for treatment of opioid use disorder (OUD). Prior research found substantial variation in changes to medication use for OUD associated with waiver implementation. The objective of this study was to identify strategies that states undertook as part of their waivers that were associated with increases in methadone and buprenorphine treatment in eight waiver states (Indiana, Louisiana, New Hampshire, New Jersey, Pennsylvania, Virginia, Washington, and West Virginia).

In this mixed-methods study, we combined quantitative difference-in-differences analyses of 2016-2021 Medicaid data with qualitative analyses of states' waiver application documents (N = 8) and interviews (N = 23) with individuals involved in waiver implementation.

SUD waiver implementation was associated with increased use of methadone in Virginia (estimate: 15.4 percentage points [pp]; p < 0.001), Indiana (estimate: 13.2 pp; p < 0.001), West Virginia (estimate: 9.5 pp; p < 0.001), Louisiana (estimate: 7.2 pp; p < 0.001), and New Jersey (estimate: 4.2 pp; p < 0.05). Qualitative information indicated that these states used a variety of strategies, including adding coverage, increasing reimbursement rates, and engaging providers and managed care organizations. By contrast, we observed limited or no strategies to increase the use of methadone in the other states. SUD waiver implementation was associated with increased buprenorphine prescribing in Pennsylvania (estimate: 5.2 pp; p < 0.001), Washington (estimate: 5.2 pp; p < 0.001), New Hampshire (estimate: 4.4 pp; p < 0.01), Louisiana (estimate: 4.2 pp; p < 0.01), and Indiana (estimate: 4.2 pp; p < 0.01). Qualitative analyses suggested that states with and without increases in this outcome implemented similar changes (e.g., education and training activities).

Qualitative findings helped explain state-level variation in methadone treatment following SUD waiver implementation but not for buprenorphine. Strategies identified in higher-performing states may offer useful insights for other states aiming to expand access to methadone for OUD.