The Impact of Medicaid Expansion on Congenital Heart Surgery Outcomes: Data From the Society of Thoracic Surgeons Database.

Background: The Affordable Care Act expanded Medicaid eligibility and increased public insurance coverage for children across the United States. As only a subset of states adopted expansion of coverage, disparities in insurance coverage between expansion and nonexpansion states emerged. We examined the association between Medicaid expansion and cardiac surgery outcomes to understand the impact of Medicaid expansion in a medically complex pediatric population. We hypothesized that expansion of Medicaid eligibility would be associated with greater improvement in surgical outcomes.

Methods: The Society of Thoracic Surgeons Congenital Heart Surgery Database was used to evaluate perioperative outcomes for children 0 to 18 years undergoing cardiac surgery between January 2010 and December 2019. We used a difference-in-differences (DiD) design to estimate the impact of Medicaid expansion on surgical outcomes by comparing changes in outcomes between individuals in expansion states and those in nonexpansion states, both before and after the expansion. Outcomes included operative mortality, major complications and postoperative length of stay (PLOS).

Results: The interaction between Medicaid expansion and time period post- vs preexpansion was not significant for any of the outcome variables. The odds ratio (OR) for mortality related to the Medicaid expansion was 1.12 (confidence interval [CI], 0.95-1.32, P = .161). For major complications, the OR was 0.99 (CI, 0.90-1.09, P = .770). For PLOS, the incidence rate ratio was 1.02 (CI, 0.99-1.05, P = .141).

Conclusions: There was an overall decline in congenital heart surgery mortality over time; however, states that expanded Medicaid eligibility did not experience a greater improvement in mortality relative to states that did not expand eligibility. Similarly, there was no significant difference in major complications or PLOS related to Medicaid expansion. Further studies are needed to examine long-term outcomes and the larger spectrum of accessibility to congenital cardiac care which may benefit from insurance coverage.