Differences in criminal activity between heroin abusers and subjects without psychiatric disorders--analysis of 578 detainees in Bilbao, Spain.

The association between drug abuse and criminal activity has been deeply established, but the nature of this relationship is controversial. The incidence and types of criminal activity were analyzed in 837 arrests of 578 subjects who were also interviewed for psychiatric diagnosis and evaluation of criminal responsibility. There was a significant prevalence of heroin abuse/dependence (50.5%) in the sample. Another 124 subjects (21.5%) in whom no psychiatric disorder could be observed were considered as the control group. Heroin abusers were younger (26 years, SD 5.9) than controls (29 years, SD 11.2) and showed some different ethnic characteristics. Heroin abuse/dependence was the most important risk factor (O.R. = 10.15) for criminal recidivism. Females were more related to nonviolent criminal activity than males. There was a higher incidence of offenses against property among heroin abusers (burglary 57.8%; robbery 19.5%) than in the control group (burglary 15.3% robbery 4.8%). In contrast, aggression or resistance to police authorities and nonfatal offenses against persons were more frequent among controls (12% and 13.7%, respectively) than among heroin abusers (3.7% and 3%, respectively). The results of this study confirm the hypothesis of a relationship between criminal activity and heroin abuse/dependence, probably based on financial needs. However, the association seems not to be a single and direct cause-effect relationship, as other factors show influence on the criminal activity.