State earned income tax credits and suicidal behavior: A repeated cross-sectional study

Suicide is an increasingly common cause of death in the United States and recent increases in suicide rates disproportionately impact low income individuals. We sought to assess the impact of income support in the form of state earned income tax credit policies on suicide-related behaviors. This state-level study used repeated cross-sectional data from vital records and the National Survey of Drug Use and Health data representative at the state-level. The population included adults who either died by suicide or were selected for in-person NSDUH interviews between 2008 and 2018. Exposure was measured as the generosity of a refundable state earned income tax credit policy measured as a percentage of the federal policy. Outcomes assessed were suicidal ideation, suicidal planning, non-fatal suicide attempt, suicide deaths, and combined fatal and non-fatal suicide attempts. Analyses were performed between April and June 2020. A 10 percentage-point increase in the generosity of state earned income tax credit was associated with lower frequency of non-fatal suicide attempts (prevalence ratio [PR] = 0.96; 95% CI: 0.93-0.99), combined fatal and non-fatal suicide attempts (PR = 0.96; 95% CI: 0.93-0.99), and suicide deaths (PR = 0.99; 95% CI: 0.99-1.00). This translates to 4 fewer suicide attempts per 10,000 population each year. Generous state earned income tax credit policies are associated with reductions in the frequency of most severe suicidal behavior. Income support policies may be one way to reduce suicide attempts and death, especially among low-income adults.