Revisiting the Connection Between State Medicaid Expansions and Adult Mortality

Charles J. Courtemanche, University of Kentucky; Jordan W. Jones, USDA Economic Research Service; Antonios M. Koumpias, University of Michigan-Dearborn; and Daniela Zapata, AIR

Having Medicaid coverage could reduce mortality risk by improving people’s access to medical care, which in turn may lead to improved physical and mental health. However, whether Medicaid in fact reduces adult mortality is the subject of debate in the literature.

The purpose of this paper published by the National Bureau of Economic Research was to examine the effect of the largest state Medicaid expansions in the 1990s and 2000s on all-cause, healthcare-amenable, non-healthcare-amenable, and HIV-related adult mortality using state level mortality data. The authors utilized the synthetic control method to estimate effects for each treated state separately and the generalized synthetic control method to estimate average effects across all treated states.

Using a 5% significance level, the authors found no evidence that Medicaid expansions affected any of the outcomes in any of the treated states or all of them combined. Moreover, there was no clear pattern in the signs of the estimated treatment effects. These findings imply that evidence that pre-ACA Medicaid expansions to adults saved lives is not as clear as previously suggested.

Daniela Zapata
Principal Researcher