How did Medicaid expansion under the Affordable Care Act impact health insurance coverage, cost and mental health? That is the question asked by Andreyeva, Rochford and Marthey (2025). They use 2011-2019 data from the Behavioral Risk Factor Surveillance System (BRFSS) to examine outcomes for Americans aged 26–54 with at least one child living in the household. They find that:
Medicaid expansion was associated with a 13.4 percentage point (pp) increase in the probability of reporting any health insurance (p < 0.001), an 11.3 pp decline in the probability of reporting a cost barrier (p < 0.001), and a 2.4 pp decrease in the probability of reporting days in poor mental health (p = 0.028) among low-income parents. Our results also suggest parents who were married and those identifying as non-Hispanic white (relative to Hispanic and non-Hispanic other/multiple race) experienced the largest increases in health insurance coverage.
You can read the full paper here.
Currently, most states have implemented Medicaid expansion [see map] with the exception of Kansas, Texas, Wisconsin, Wyoming, and most of the southeastern US (AL, FL, GA, MS, SC, TN).
