Association of Medicare Advantage vs Traditional Medicare with Clinical Outcomes Among Patients Hospitalized for Substance Use Disorders.

Abstract

Medicare Advantage (MA) includes incentives to reduce health care spending and insures over half of Medicare eligible adults. Substance use disorders (SUD) are common in this population. To compare clinical outcomes between MA and traditional Medicare beneficiaries hospitalized with SUD. Retrospective cohort. Medicare beneficiaries hospitalized for alcohol withdrawal or opioid overdose from 2016 to 2021. Primary outcomes included mortality and all-cause readmissions within 30 days of discharge. Secondary outcomes included use of SUD medications. Of 104,833 beneficiaries hospitalized for alcohol withdrawal (mean age 62.1 [SD 11.5] years, 71.8% male) and 75,463 hospitalized for opioid overdose (mean age 64.5 [SD 12.5] years, 40.8% male), 36.4% and 37.3% were enrolled in MA, respectively. Adjusted rates of 30-day mortality were lower in MA for alcohol withdrawal (unadjusted 2.5% in MA vs 2.4% in traditional Medicare; adjusted difference -0.27 pp [95% CI -0.47, -0.08]) but similar for opioid overdose (7.8% in MA vs 7.9% in traditional Medicare; adjusted difference -0.13 pp [-0.54, 0.27]). Rates of 30-day readmissions were lower in MA for both alcohol withdrawal (12.3% in MA vs 13.7% in traditional Medicare; adjusted difference -1.01 pp [95% CI -1.44, -0.59]) and opioid overdose (14.8% in MA vs 17.6% in traditional Medicare; adjusted difference -1.93 pp [95% CI -2.49, -1.37]). Enrollment in MA was associated with lower use of medications for alcohol use disorder (unadjusted 9.6% in MA vs 11.3% in traditional Medicare; adjusted difference -1.66 pp [95% CI -2.72, -0.60]) but higher use of medications for opioid use disorder (unadjusted 4.9% in MA vs 4.2% in traditional Medicare; adjusted difference, 0.82 pp [95% CI 0.08, 1.57]). Compared to traditional Medicare, MA was associated with modestly lower 30-day mortality after alcohol withdrawal, lower 30-day readmission rates after alcohol withdrawal and opioid overdose hospitalizations, and mixed findings on medication use.