Was Unstable Medicaid Coverage among Older Medicare Beneficiaries Associated with Worse Clinical Outcomes? Evidence from the Delivery of Breast Cancer Care

Background: Medicare and Medicaid dually eligible beneficiaries (duals) could experience Medicaid coverage changes without losing Medicaid. It is unknown whether health care use and clinical outcomes among elderly duals with coverage changes would be like those among duals without coverage changes or duals ever lost Medicaid and whether various types of unstable coverage due to income/asset changes are associated with worse clinical outcomes. Objectives: Examine the associations of unstable Medicaid coverage with clinical outcomes among older Medicare beneficiaries. Research Design: Population-based cohort study. Subjects: A total of 131,202 women newly diagnosed with breast cancer at 65 years and older between 2007 and 2015 were identified from the Surveillance, Epidemiology, and End Results-Medicare linked database. Measures: We examined 2 types of unstable Medicaid coverage: (1) those who had changes in the types of Medicaid support they received and (2) those who ever lost Medicaid. We examined outcomes that predict better cancer survival and involve the use of inpatient and outpatient services and prescription drugs: early diagnosis, receiving surgery, receiving radiation, hormonal therapy adherence, and discontinuation. We used logistic regressions to estimate the predicted probabilities of outcomes for dual groups. Results: Duals had poorer outcomes than those who were "never dual." Women with the 2 types of unstable Medicaid coverage had similarly worse outcomes than those with stable coverage. Those with stable coverage had similar outcomes regardless of the generosity of Medicaid support. Conclusions: These patterns are concerning and, in the context of well-defined clinical guidelines for beneficial treatments that extend survival, point to the importance of stable insurance coverage and income.