Impact of medicaid expansion on disparities in revascularization in patients hospitalized with acute myocardial infarction

INTRODUCTION: Blacks are more likely to live in poverty and be uninsured, and are less likely to undergo revascularization after am acute myocardial infarction compared to whites. The objective of this study was to determine whether Medicaid expansion was associated with a reduction in revascularization disparities in patients admitted with an acute myocardial infarction. METHODS: Retrospective analysis study using data (2010–2018) from hospitals participating in the University Health Systems Consortium, now renamed the Vizient Clinical Database. Comparative interrupted time series analysis was used to compare changes in the use of revascularization therapies (PCI and CABG) in white versus non-Hispanic black patients hospitalized with either ST-segment elevation (STEMI) or non-ST-segment elevation acute myocardial infarctions (NSTEMI) after Medicaid expansion. RESULTS: The analytic cohort included 68,610 STEMI and 127,378 NSTEMI patients. The percentage point decrease in the uninsured rate for STEMIs and NSTEMIs was greater for blacks in expansion states compared to whites in expansion states. For patients with STEMIs, differences in black versus white revascularization rates decreased by 2.09 percentage points per year (95% CI, 0.29–3.88, P = 0.023) in expansion versus non-expansion states after adjusting for patient and hospital characteristics. Black patients hospitalized with STEMI in non-expansion states experienced a 7.24 percentage point increase in revascularization rate in 2014 (95% CI, 2.83–11.7, P < 0.001) but did not experience significant annual percentage point increases in the rate of revascularization in subsequent years (1.52; 95% CI, -0.51–3.55, P = 0.14) compared to whites in non-expansion states. Medicaid expansion was not associated with changes in the revascularization rate for either blacks or whites hospitalized with NSTEMIs. CONCLUSION: Medicaid expansion was associated with greater reductions in the number of uninsured blacks compared to uninsured whites. Medicaid expansion was not associated, however, with a reduction in revascularization disparities between black and white patients admitted with acute myocardial infarctions.