University of Groningen: The link between poor sleep and aggression

Sleep plays an important role in mental health, among which emotion regulation and self-control. Disrupting your sleep could therefore contribute to heightened aggression. Maaike van Veen’s research shows that there is indeed a clear and consistent link between the two, especially for people who are psychologically vulnerable. The targeted treatment of sleep issues offers a new possibility to reduce anger, hostility, and aggressive behaviour, especially in psychiatry and more specifically forensic psychiatry.

The thesis describes several study methods to research the link between poor sleep and aggression. Two systematic reviews and meta-analyses were performed to summarize previous research. Previous research focused on the link between the quality and duration of sleep and various levels of aggression, like anger and hostility. Van Veen compiled a large number of observational and experimental studies, which together show a clear and consistent link between poor or shortened sleep and a high level of aggression. This link seems to be more apparent in people who are psychologically vulnerable.

In addition, she studied the link between quality of sleep, impulsivity, and aggression in a cohort of forensic psychiatric patients. Poor quality of sleep was related to a higher level of self-reported impulsivity and aggression. This was also true in longitudinally, in which it was found that poor quality of sleep in these patients was related to a higher level of aggression after one year. These links were not explained by the psychiatric diagnosis or general psychopathology.

Although this thesis does not directly study the causal link between sleep and aggression, the results do show that improving sleep habits could be a new and important strategy in reducing and preventing anger, hostility, and aggressive behaviour, especially in psychiatric and forensic psychiatric patients.