Racial and ethnic differences in medications for opioid use disorder and overdose in 11 state Medicaid programs from 2016 to 2020

INTRODUCTION: Access to medications for opioid use disorder (MOUD) varies across racial and ethnic groups. As the largest payer for MOUD, Medicaid has potential to ensure access for all enrollees. We aimed to quantify recent trends and state variation in MOUD use by race and ethnicity in Medicaid. METHODS: Using a distributed research network, we conducted a cross-sectional study of 11 states' Medicaid data from 2016 to 2020. Among enrollees diagnosed with opioid use disorder (OUD), we measured the percent receiving MOUD (overall; and methadone, buprenorphine, naltrexone, separately), continuity of MOUD for ≥180 days, and claims-based overdose event rates. We estimated logistic regression models in each state with fixed effects for year, race/ethnicity, and year and race/ethnicity interaction terms to examine changes in demographic differences in outcomes over time, adjusting for patient characteristics. We pooled estimates using random effects meta-analyses. RESULTS: Of the 542,414 enrollees with OUD in 2020, 430,891 (79.4%) were non-Hispanic white, 77,952 (14.4%) were non-Hispanic Black, 17,094 (3.2%) were Hispanic, and 16,477 (3.0%) had other race or ethnicity. MOUD use increased among enrollees in all racial and ethnic groups over time. The share of non-Hispanic white enrollees diagnosed with OUD receiving MOUD increased from 52.3% to 68.8% from 2016 to 2020 while the percent of non-Hispanic Black enrollees receiving MOUD from 37.2% to 49.7% during that period. Differences were widest for buprenorphine versus methadone or naltrexone. In adjusted analyses, Hispanic and Non-Hispanic Black enrollees were less likely to receive MOUD (adjusted odds ratios (AOR) = 0.67 [95 CI 0.49-0.91] and AOR = 0.41 [95 CI 0.33-0.52], respectively) compared to non-Hispanic white enrollees in 2016. Differences in receipt of MOUD did not change from 2016 to 2020. Non-Hispanic Black enrollees were less likely to have continuous MOUD relative to non-Hispanic white enrollees (AOR = 0.68 [95 CI 0.61-0.77)]. Overdose events peaked in 2017 for all racial and ethnic groups and were highest for Hispanic enrollees in 2020. CONCLUSION: MOUD increased among all racial and ethnic groups in 11 state Medicaid programs from 2016 to 2020. Yet, racial and ethnic differences in MOUD persisted, especially for buprenorphine. Our findings can inform Medicaid efforts to improve access to MOUD for all enrollees affected by OUD.