Handgun Divestment and Risk of Suicide

Firearm ownership is strongly related to suicide risk, yet little is known about how much risk declines when ownership ends (“divestment”). METHODS: Using data from 523,182 handgun owners, we estimated the effect of divesting and remaining divested versus never divesting on the risk of suicide and firearm-specific suicide. We used pooled logistic regression with inverse probability weighting, adjusting for demographic and area-level measures. RESULTS: The 5-year risk of suicide death was 25.6 (95% confidence interval [CI] = 15.1, 37.2) per 10,000 persons with divestment and 15.2 (95% CI = 13.2, 17.3) per 10,000 persons with no divestment, corresponding to a risk difference of 10.4 (95% CI = 0.7, 21.1) per 10,000 persons. The 5-year risk of firearm-specific suicide death was 6.3 (95% CI = 1.4, 11.9) per 10,000 persons with divestment and 12.9 (95% CI = 11.0, 14.6) per 10,000 persons with no divestment, corresponding to a risk difference of –6.6 (95% CI = –11.4, –0.1) per 10,000 persons. Comparing divestment to no divestment, risks were elevated for deaths due to other causes proposed as negative control outcomes; we incorporated these estimates into a series of bias derivations to better understand the magnitude of unmeasured confounding. CONCLUSIONS: Collectively, these estimates suggest that divestment reduces firearm suicide risk by 50% or more and likely reduces overall suicide risk as well, although future data collection is needed to fully understand the extent of biases such as unmeasured confounding.