The Effects of the Affordable Care Act on Utilization of Bariatric Surgery.

INTRODUCTION The Affordable Care Act (ACA) expanded Medicaid (ME) and instituted Essential Health Benefits (EHB) that included bariatric surgery coverage on a state-by-state opt-in basis, increasing insurance coverage of bariatric surgery. MATERIALS AND METHODS Using a difference-in-differences framework, changes in bariatric surgery rates, defined as utilization in the population of people with obesity, before and after the ACA were evaluated in four states. Bariatric surgery procedure data were taken from the Healthcare Cost and Utilization Project's State In-patient Database 2012-2015. Adjusted multivariable regressions were run in the Medicaid and commercially insured populations. RESULTS We identified 36,456 bariatric surgeries across the 286 Health Service Areas and time periods, with 31,732 covered by commercial insurers and 4724 covered by Medicaid. An unadjusted increase in utilization rates was seen in the Medicaid and Commercial populations in both ME- and EHB-covered states as well as non-expansion and EHB opt-out states over time. In the Medicaid population, after adjusting for confounders, there was a significant increase of 24.77 cases per 100,000 people with obesity (95% confidence interval: 12.41, 37.13) in the expansion states relative to the control and pre-period. The commercial population experienced a nonsignificant change in the rates of bariatric surgery, decreasing by 2.89 cases per 100,000 people with obesity (95% confidence interval: - 21.59, 15.81). CONCLUSIONS There was a significant increase in bariatric surgery rates among Medicaid beneficiaries associated with Medicaid expansion, but there was no change among the commercially insured.