The role of alcohol in suicide: a case-control psychological autopsy study

Background. The purpose of the study was to estimate the proportion of alcohol abuse and dependence (AAD) among suicides and controls, and to compare the incidence of AAD documented by clinicians with diagnoses derived from a research protocol. Method. AAD according to DSM-IV was diagnosed on the basis of interviews with relatives of people who committed suicide and with controls. A total of 427 people who committed suicide during one year were paired by region, gender, age and nationality with controls randomly selected from general practitioners' lists. Results. Alcohol abuse was found in 10% and alcohol dependence in 51% of suicide cases. The corresponding figures for controls were 7% and 14% respectively. AAD was a statistically significant predictor of completed suicides, while abstinence was a significant predictor for female suicides and former use a significant predictor for older male suicides. AAD was diagnosed in 68% of male and 29% of female suicides. Middle-aged (35–59 years) males who committed suicide had the highest risk of alcohol dependence. Among suicide cases only 29% had received a lifetime diagnosis of AAD, against 23% of controls. Conclusions. AAD was significantly more prevalent among suicides than controls. Overall, the proportion of male suicides affected by alcohol was the same in the present psychological autopsy study as in our previous findings for Estonia on the aggregate level, while the share of female suicides with an AAD diagnosis was dramatically higher on the individual level. AAD is markedly underdiagnosed by general practitioners and clinicians.