The Impact of Medicaid Expansion for Adults Under the ACA on Preventive Care for Children: Evidence From the Southern United States.

INTRODUCTION The Affordable Care Act of 2010 expanded Medicaid to low-income adults at or below 138% of the Federal Poverty Line (FPL). The aim of this study was to examine if expanding Medicaid to adults had an impact on preventive health care utilization of children from low-income families (focusing on families with annual incomes 0%-99% and 100%-199% of the FPL). METHODS This study used data from the 2016 and 2017 National Survey of Children's Health and a quasi-experimental difference-in-differences method. The dependent variable was the number of preventive care visits in the past year and the primary independent variable was the Medicaid expansion status of the state. Louisiana expanded Medicaid in 2016 (treatment group) and neighboring nonexpansion states of Texas and Mississippi constituted the control group. Differences in dependent variable were calculated between survey years 2016 and 2017. RESULTS In Louisiana, the change in the predicted probability of at least 1 preventive care visit among children of ages 0-17 years, from 0% to 99% FPL families, was higher by 26 percentage points after Medicaid was expanded (2017 vs. 2016), as compared with the change in the predicted probability (2017 vs. 2016) of at least 1 preventive care visit among children of ages 0-17 years, from 0% to 99% FPL families in the nonexpansion states, Texas and Mississippi. CONCLUSIONS Children in poverty residing in a Medicaid expansion state, Louisiana, had increased likelihood of having an annual preventive care visit after expansion of Medicaid eligibility under the Affordable Care Act, as compared with children in nonexpansion states. Thus, this study showed that the implications of the public health insurance expansion for adults were not limited to adult health outcomes, but extended to children's health care utilization.