Childhood origins of violent behaviour in adults with schizophreniform disorder

Abstract

Background: People with psychosis have an elevated risk of violence.

Aims: To examine whether violent behaviour in adults with psychosis can be accounted for by psychotic symptoms or physical aggression in childhood.

Method: We used data from a prospective longitudinal study of a complete birth cohort born in New Zealand. When cohort members were 26 years old, information was obtained on past-year psychiatric diagnosis of schizophreniform disorder and on violent behaviour. Childhood psychotic symptoms were measured at age 11 years using a diagnostic interview, and childhood physical aggression was assessed by teachers when cohort members were aged 7, 9 and 11 years.

Results: Participants with schizophreniform disorder were more likely to be violent than participants without, even after controlling for sociodemographic variables and concurrent substance dependence disorders. Childhood psychotic symptoms were a strong risk factor for violence in adults with schizophreniform disorder, as was childhood physical aggression, although to a lesser extent.

Conclusions: Violence by individuals with schizophreniform disorder could be prevented by monitoring early signs of psychotic symptoms and by controlling childhood physical aggression.