Abstract
OBJECTIVE: Prior research has shown that Medicaid expansion is linked with slightly reduced suicide rates at the state level. This study aimed to investigate the association between Medicaid expansion and suicide rates at the county level, as well as disparities based on rurality and areas with a shortage of mental health professionals. METHODS: In this cross-sectional study, the authors conducted a difference-in-differences analysis, with regression-adjusted ordinary least squares and fixed effects of county and year, to compare changes in county-level suicide mortality rates among nonelderly adults before and after Medicaid expansion. Whether these changes differed by rurality and by mental health professional availability was also examined. RESULTS: Among 3,068 unique counties included in the analysis, on average, 50.0% of residents were male, 17.1% ages ≥65 years, 34.8% high school graduates, and 76.8% non-Hispanic White. The estimated suicide incidence rate per 100,000 population was 17.2 across all counties from 2007 to 2021. Medicaid expansion was not significantly associated with suicide rates. However, the three-way interaction term indicated a significant decrease in suicide rates after Medicaid expansion in metropolitan counties without mental health professional shortages (adjusted coefficient=-1.32, 95% CI=-2.37 to -0.28, p=0.014). CONCLUSIONS: These findings suggest that Medicaid expansion may have a greater impact in areas with more resources and infrastructure to provide mental health care. Further investigation is needed into the mechanisms that drive these differences.