Abstract
Background: Insomnia is common in forensic psychiatric patients. Not only does insomnia severely impair general mental health, but it has specifically been associated with poor emotion regulation and self-control, potentially leading to problems in impulsivity, hostility, and even aggression. Cognitive behavioral therapy for insomnia (CBT-I) could therefore be beneficial in this patient group. Methods: We conducted a 14-week randomized controlled trial of the effects of cognitive behavioral therapy for insomnia (CBT-I) on sleep, general psychopathology, hostility, impulsivity, and aggression in 31 male forensic psychiatric patients. Results: The CBT-I group (n = 11) showed a stronger reduction in self-reported insomnia symptoms and hostility than the waitlist group (n = 11). No differences were found in post-treatment self-reported general psychopathology, impulsivity, or aggression, nor on actigraphy-measured sleep efficiency. Conclusions: This study demonstrates the effectiveness of CBT-I in forensic psychiatric patients and indicates the importance of insomnia treatment in this population, especially considering the effect on hostility.