Violent behavior during sleep: prevalence, comorbidity and consequences.

BACKGROUND: Violent behaviors during sleep (VBS) are consequences of several sleep disorders but have received little attention in epidemiologic studies. This study aims to determine the prevalence of VBS in the general population and their comorbidity, familial links, course and treatment.

METHODS: Random stratified sample of 19,961 participants, 15 years and older, from the general population of Finland, Germany, Italy, Portugal, Spain and the United Kingdom were interviewed by telephone using the Sleep-EVAL Expert System. They answered a questionnaire on VBS, their consequences and treatment. Parasomnias and sleep and mental disorders were also evaluated.

RESULTS: VBS was reported by 1.6% (95% confidence interval: 1.4-1.7%) of the sample. VBS was higher in subjects younger than 35 years. During VBS episodes, 78.7% of VBS subjects reported vivid dreams and 31.4% hurt themselves or someone else. Only 12.3% of them consulted a physician for these behaviors. In 72.8% of cases, VBS were associated with other parasomnias (highest odds of VBS for sleepwalking and sleep terrors). Family history of VBS, sleepwalking and sleep terrors was reported more frequently in VBS than in non-VBS subjects with odds of 9.3, 2.0 and 4.2, respectively.

CONCLUSIONS: VBS are frequent in the general population and often associated with dream-enactment, sleepwalking and sleep terrors. High frequency of VBS, sleepwalking and sleep terrors in family of VBS subjects indicated that some families have a greater vulnerability to sleep disorders involving motor dyscontrol. Subjects who consulted a physician for these behaviors mostly received inappropriate or no support, indicating a lack of knowledge about VBS.