Association of rates of household handgun ownership, lifetime major depression, and serious suicidal thoughts with rates of suicide across US census regions.
OBJECTIVE
Cross sectional studies in the United States often find a significant positive association between levels of household firearm ownership and suicide rates. This study investigates whether the association can be explained by differences in levels of mental health.


METHODS
The relationship between household handgun ownership and overall suicide rates across United States regions after accounting for two mental health variables-lifetime prevalence of major depression and serious suicidal thoughts-were examined. Analyses also add another control variable (urbanization, education, unemployment, or alcohol consumption). Data on mental health variables come from the National Comorbidity Study, conducted in the early 1990s. Data on household handgun ownership come from the General Social Surveys.


RESULTS
Across the nine regions for the early 1990s (n = 9), household handgun ownership rates are positively correlated with the suicide rate (r = 0.59) and are not correlated with either the lifetime prevalence of major depression or suicidal thoughts. After controlling for major depression and suicidal thoughts (and any of the four additional control variables), handgun ownership rates remain significantly associated with the overall suicide rate.


CONCLUSIONS
In United States regions with higher levels of household handgun ownership, there are higher suicide rates. This relationship cannot be explained by differences in the prevalence of two mental health indicators-lifetime rates of either major depression or suicidal thoughts.
Hemenway
D
D
Harvard School of Public Health, Boston, MA 02115, USA. hemenway@hsph.harvard.edu
Miller
M
M
D003866:Depressive Disorder / Q000453:epidemiology / Q000523:psychology*; D005260:Female; D005389:Firearms / Q000592:standards*; D006708:Homicide / Q000706:statistics & numerical data*; D006801:Humans; D015994:Incidence; D008297:Male; D008603:Mental Health; D012307:Risk Factors; D013405:Suicide / Q000523:psychology* / Q000706:statistics & numerical data; D013850:Thinking; D014481:United States / Q000453:epidemiology