STOCKHOLM.– A study at Karolinska Institutet of 133 violent offenders in Sweden shows that 78 (58%) had consumed alcohol within 24 hours before the violent act. A large majority of the offenders were men with psychiatric diagnoses and most of the victims were known to them.  

A 13.2-fold increase of risk of violence was found within 24 hours of alcohol consumption. The relative risk of violence was based on comparison to each individual's usual frequency of alcohol use during the previous year, in a case-crossover analysis.  

Use of other drugs like benzodiazepines and antidepressants in regular doses was associated with a decreased risk of violence. Contrary to other studies the risk for criminal violence was not increased if the consumption of alcohol was combined with benzodiazepines.  

"Alcohol seems to have the largest triggering effect on violence compared to other substances we investigated. This suggests that treatment for individuals at risk for violence should be focused on decreasing their alcohol consumption", says Ulrika Haggård-Grann of the Karolinska Institutet.