Sexual offending in women and psychiatric disorder: a national case-control study

Women commit 4-5% of all sexual crimes, but there is considerable uncertainty about associations with psychosis and substance abuse. We examined the prevalence of psychiatric hospitalization, psychotic disorders, and substance abuse in a nationwide sample of female sexual offenders. We obtained data from Swedish national registers for criminal convictions, hospital discharge diagnoses, and demographic and socioeconomic factors between 1988 and 2000, and merged them using unique identifiers. Convicted female sexual offenders (n = 93) were compared with all females convicted of non-sexual violent offences (n = 13,452) and a random sample of general population women (n = 20,597). Over 13 years, 36.6% of female sexual offenders had been admitted to psychiatric hospital and 7.5% been discharged with a diagnosis of a psychotic disorder. Compared to non-sexual violent offenders, there were no significant differences in the proportion diagnosed with psychosis or substance abuse. Compared to women in the general population, however, there was a significantly increased risk in sex offenders of psychiatric hospitalization (age-adjusted odds ratio [AOR] = 15.4; 95% CI: 10.0-23.7), being diagnosed with a psychotic disorder (AOR = 16.2; 95% CI: 7.2-36.4), and with substance use disorders (AOR = 22.6; 95% CI: 13.0-39.1). We conclude that the prevalence of psychotic and substance use disorders was not different between sexual offenders and other violent offenders, suggesting non-specificity of sexual offending in women. Nevertheless, substantially increased prevalences of psychiatric disorder, underline the importance of screening and assessment of female sexual and other violent offenders.