Association of Medicaid Eligibility With Surgical Readmission Among Medicare Beneficiaries

Key Points Question In risk-adjustment models of surgical readmissions, is dual eligibility for Medicare and Medicaid associated with all-cause 30-day readmission after surgery? Findings In this cohort study of 55 651 Medicare beneficiaries, dual eligibility was associated with readmission when using standard claims-based risk adjustment, but the association was attenuated when adjusting for additional clinical risk factors measured by a statewide clinical registry. Adjusting for dual eligibility for Medicare and Medicaid had little association with hospital rankings by risk-adjusted readmission rate. Meaning Dual-eligibility status may reflect unmeasured clinical risk instead of social risk factors associated with readmission after surgery.