Using a Firearm in a Suicide More Likely as Blood Alcohol Increases up to a Certain Level

The probability of a firearm-involved suicide increased with alcohol consumption until a certain blood alcohol concentration (BAC) level, which depended on gender, at which point the probability decreased. These results from a study were published in JAMA Network Open.

Investigators from the Institute for Mental Health Policy Research in Canada conducted this cross-sectional study using data from the United States National Violent Death Reporting System (NVDRS). Decedents (N=58,095) who died in a solitary suicide and had a BAC of 0.01 g/dL or greater were evaluated for the likelihood of using a firearm as the suicide method on the basis of BAC.

Decedents were men (n=45,959) with mean age 42.6 (SD, 14.8) years and women (n=12,136) aged 44.2 (SD, 13.8) years among whom 53.8% and 29.7% used a firearm, respectively. The men and women had similar BAC levels on average (mean range, 0.14-0.15 g/dL).

The relationship between BAC and firearm use was nonlinear, in which there was a dose-response curve with an inverted U-shape. As BAC increased, so did the probability of firearm use until a BAC of 0.40 g/dL for men and 0.30 g/dL for women, at which point the probability decreased. Only a small proportion of suicides occurred among these BAC levels for both men (1.3%) and women (6.2%).

Most suicides occurred at BAC 0.011-0.199 g/dL (70.7%-72.8%) or 0.20-0.399 g/dL (25.8%-28.1%).

The major limitation of this study was that toxicology testing in suicides is based on local resources, so these data are likely incomplete.

This study found that at lower BAC levels, the probability of using a firearm as the method of suicide increased until a certain BAC level. These findings led the study authors to conclude, “In this cross-sectional study of suicide decedents who had consumed alcohol prior to their death, we found that the more alcohol consumed, the higher the probability of using one of the most lethal methods of suicide — a firearm (90% of suicide attempts involving a firearm will result in death). This association suggests that scalable interventions targeting heavy alcohol use (eg, alcohol control policies) may potentially reduce the suicide mortality rate in the US, which appears to be increasing again after decreasing for the past 3 years.”

This article originally appeared on Psychiatry Advisor