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

Abstract

Background: 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.

Objective: To compare clinical outcomes between MA and traditional Medicare beneficiaries hospitalized with SUD.

Design: Retrospective cohort.

Patients: Medicare beneficiaries hospitalized for alcohol withdrawal or opioid overdose from 2016 to 2021.

Measures: Primary outcomes included mortality and all-cause readmissions within 30 days of discharge. Secondary outcomes included use of SUD medications.

Results: 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]).

Conclusions: 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.