When compared with non-expansion states, US states that expanded Medicaid during the implementation of the Affordable Care Act (ACA) had a significantly greater reduction in the percentage of uninsured patients hospitalized for major cardiovascular (CV) events, according to the results of a study published in JAMA Network Open.

Cardiovascular disease is the most prevalent primary diagnosis for hospital discharges in the United States. Insurance status has a significant impact on patient outcomes, and researchers sought to assess the association of the ACA Medicaid expansion with the rates of uninsured patients hospitalized for major CV events. Using inpatient data from the Healthcare Cost and Utilization Project in 30 states, researchers conducted a difference-in-difference analysis of Medicare and non-Medicare hospitalizations in 2014 and from 2009 to 2013, respectively, for stroke, heart failure, and/or acute myocardial infarction.

In 2014, the 17 expansion states had 281,184 non-Medicare hospitalizations; the 13 non-expansion states had 243,664 non-Medicare hospitalizations. When compared with the non-expansion states, the 17 expansion states showed a 5.8% reduction in uninsured hospitalizations in 2014 (-0.058; 95% CI, -0.075 to -0.042; P <.001), and an 8.4% increase in Medicaid share (0.084; 95% CI, 0.065-0.102; P <.001). Rates of in-hospital mortality did not significantly change post-expansion for the non-expansion states (4.0% before vs 4.0% after) or the expansion states (3.8% before vs 3.7% after).

Continue Reading

Related Articles

Study investigators concluded that choosing to expand Medicaid during the ACA implementation in 2014 did significantly reduce the number of uninsured hospitalizations, but was not associated with in-hospital mortality changes. They believe that “[f]urther research is necessary to determine how state-level policy decisions regarding ACA implementation could differentially influence short-term and long-term CV outcomes before, during, and after hospitalization.”


Akhabue E, Pool LR, Yancy CW, Greenland P, Lloyd-Jones D. Association of state medicaid expansion with rate of uninsured hospitalizations for major cardiovascular events, 2009-2014JAMA Network Open. 2018;1(4):e181296. doi:10.1001/jamanetworkopen.2018.1296.