Effects of State-level Medicaid Expansion on Veterans Health Administration Dual Enrollment and Utilization: Potential Implications for Future Coverage Expansions.

OBJECTIVE: The objective of this study was to examine how pre-Affordable Care Act (ACA) state-level Medicaid expansions affect dual enrollment and utilization of Veterans Health Administration (VA) and Medicaid-funded care. RESEARCH
DESIGN: We employed difference-in-difference analysis to determine the association between pre-ACA Medicaid expansions in New York and Arizona in 2001 and VA utilization. Participants' dual enrollment in Medicaid and VA, the distribution of their annual hospital admissions and emergency department (ED) visits between VA and Medicaid were dependent variables. We controlled for age, race, sex, disease burden, distance to VA facilities and income-based eligibility for VA services. MEASURES: Secondary data collected from 1999 to 2006 in 2 states expanding Medicaid and 3 demographically similar nonexpansion states. We obtained residency, enrollment and utilization data from VA's Corporate Data Warehouse and Medicaid Analytic Extract files.
RESULTS: For low-income Veterans, Medicaid expansion was associated with increased dual enrollment of 4.87 percentage points (99% confidence interval: 4.48-5.25), a 4.63-point decline in VA proportion of admissions (-5.87 to -3.38), and a 11.70-point decrease in the VA proportion of ED visits (-13.06 to -10.34). Results also showed increases in the number of total (VA plus Medicaid) annual per-capita hospitalizations and ED visits among the group of VA enrollees most likely to be eligible for expansion.
CONCLUSIONS: This study shows slight usage shifts when Veterans gain access to non-VA care. It highlights the need to overcome care-coordination challenges among VA patients as states implement ACA Medicaid expansion and policymakers consider additional expansions of public health insurance programs such as Medicare-for-All.