Acute and chronic alcohol use correlated with methods of suicide in a Swiss national sample

Chronic and acute alcohol use are highly associated risk factors for suicides worldwide. Therefore, we examined suicide cases with and without alcohol use disorder (AUD) using data from the SNSF project "Suicide in Switzerland: A detailed national survey". Our investigations focus on correlations between acute and chronic alcohol use with reference to suicide and potential interactions with the methods of suicide.

We used data from the SNSF project in which all cases of registered completed suicide in Switzerland reported to any of the seven Swiss institutes of legal and forensic medicine between 2000 and 2010 were collected. We extracted cases that were tested for blood alcohol to use in our analysis. We compared clinical characteristics, blood alcohol concentrations, and methods of suicide in cases with and without AUD.

Out of 6497 cases, 2946 subjects were tested for acute alcohol use and included in our analysis. Of the latter, 366 (12.4%) persons had a medical history of AUD. Subjects with AUD significantly had higher blood alcohol concentrations and were more often in medical treatment before suicide. Drug intoxication as method of suicide was more frequent in cases with AUD compared to NAUD.

Overall, we found a high incidence of acute alcohol use at the time of death in chronic alcohol misusers (AUD). The five methods of suicide most commonly used in Switzerland differed considerably between individuals with and without AUD. Blood alcohol concentrations varied across different methods of suicide independently from the medical history in both groups.