The evolving impact of Medicaid expansion on suicide mortality: demographic and method-specific effects.

Introduction: Research suggests that Medicaid expansion may lead to population-level reductions in suicide. However, the time-varying impact on suicide rates has not been well-characterized, and it is unknown whether potential suicide reductions are limited to specific injury mechanisms. This study examined the evolving effects of Medicaid expansion on state-level suicide rates disaggregated by injury mechanism and across demographic groups.

Methods: Restricted mortality data for 2005-2021 were obtained from the National Center for Health Statistics. Difference-in-differences approaches with event study specifications were used to estimate the effects of Medicaid expansion on firearm, non-firearm, and overall suicide rates among nonelderly adults and demographic subgroups. Analyses were conducted in 2024.

Results: Medicaid expansion was associated with 1.01 fewer suicides (95% CI: -1.93, -0.10) and 0.47 fewer firearm suicides (95% CI: -1.05, 0.11) per 100,000 nonelderly adults. The protective effects of expanding Medicaid eligibility grew over time. Among demographic subgroups, reductions were largest for the population aged 18-29 years, including 2.70 fewer suicides (95% CI: -4.55, 0.86) and 1.47 fewer firearm suicides per 100,000 (95% CI: -2.67, -0.27). Expansion was also associated with fewer firearm suicides among adolescents aged 10-17 years (-0.47, 95% CI: -1.05, 0.12). There were no significant reductions in overall suicide among Black individuals (-2.05, 95% CI: -8.22, 4.11), whereas expansion was associated with 0.79 fewer suicides per 100,000 white individuals (95% CI: -1.74, 0.16).

Conclusions: Medicaid expansion resulted in fewer suicide deaths, including those involving firearms. These findings suggest that Medicaid expansion was particularly impactful in preventing suicide among young adults.