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Effects of Recent Medicaid Expansions on Infant Mortality by Race and Ethnicity
Joanne Constantin1, George L Wehby1
1Department of Health Management and Policy, College of Public Health, University of Iowa, Iowa City, Iowa.
Introduction:
The purpose of this study is to examine year-by-year effects of the 2014 Affordable Care Act Medicaid expansion on infant mortality by race and ethnicity over the first 6 years.
Methods:
Publicly available 2011-2019 Multiple Cause of Death data were extracted in October and analyzed by November 2021. A difference-in-differences event-study design compared infant mortality changes in states that expanded in 2014 to nonexpansion states.
Results:
In the main model, the 2014 Medicaid expansions were associated with a statistically significant decline in Black infants' mortality in 2018 and 2019 by 1.19 (95% CI= -2.27, -0.12) and 1.35 (95% CI= -2.45, -0.26) deaths per 1,000 live births, respectively. There was also a decline in mortality for Hispanic infants in 2015-2019, including by 0.8 (95% CI= -1.25, -0.36) and 1.28 (95% CI= -1.88, -0.68) deaths per 1,000 live births in 2015 and 2019, respectively. Overall, infant mortality declined by 0.37 (95% CI= -0.70, -0.05) deaths per 1,000 live births in 2019.
Conclusions:
The study adds evidence on the association of the Affordable Care Act Medicaid expansions with a decline in mortality of Black and Hispanic infants. The findings shed light on the importance of examining year-by-year effects over multiple years.
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