Medicaid Expansion and Overall Mortality among Individuals with Renal Cell Carcinoma

Abstract

Introduction: Renal cell carcinoma (RCC) remains a major cause to cancer-related morbidity, mortality, and economic burden in the United States. Medicaid expansion under the Affordable Care Act (ACA) increased access to insurance coverage for low-income adults, yet evidence regarding its impact on RCC survival remains limited. Objective: To evaluate the association between Medicaid expansion and overall and five-year survival among adults aged 40–64 diagnosed with RCC. Methods: We conducted a retrospective cohort study using National Cancer Database data (2006–2021). States were classified as Medicaid expansion or non-expansion using NCDB policy variables. The pre-expansion period was defined as 2006–2013 and the post-expansion period as 2014–2021. Difference-in-differences Cox proportional hazards models estimated the association between Medicaid expansion and mortality, adjusting for demographic, clinical, tumor, facility, and socioeconomic characteristics. Royston–Parmar flexible parametric models estimated absolute differences in five-year survival. Results: A total of 284,967 adults with RCC were identified. Medicaid coverage increased from 7.9% to 16.7% in expansion states and from 6.9% to 9.3% in non-expansion states (P < .001). The uninsured rate declined from 7.3% to 1.9% in expansion states, versus 8.2% to 4.7% in non-expansion states (P < .001). Medicaid expansion was associated with a 7.5% reduction in overall mortality (hazard ratio [HR], 0.93; 95% CI, 0.91–0.94; P < .001). Five-year mortality decreased by 1.4 percentage points overall (95% CI, −1.6 to −1.3; P < .001), with the largest benefit among Hispanic patients (−6.3 percentage points; 95% CI, −7.5 to −5.0; P < .001). No significant five-year survival changes were observed among non-Hispanic Black patients (−0.3 percentage points; P = .57). Conclusions: Medicaid expansion was associated with substantial improvements in insurance coverage and clinically meaningful reductions in RCC mortality, particularly among Hispanic and non-Hispanic White patients. Persistent survival gaps among non-Hispanic Black patients highlight the need for interventions beyond insurance coverage alone to achieve equity in RCC outcomes.