How common and serious are the problems of aggression and violence in a person diagnosed with schizophrenia?
Persons with schizophrenia are at increased risk for the commission of violent acts. Data from around the world suggest that they may be 4 times more likely to engage in violence than members of the general population--somewhat less if substance abuse is controlled for. However, the proportion of violence accounted for by people with schizophrenia and other psychotic disorders is small; British and Swedish studies suggest 1-2%, while a US study indicates that the attributable risk for mental disorders in general is 3-5%. Risk factors include illness-related variables (e.g., suspiciousness/persecutory delusions, hallucinations, grandiosity, excitement) and variables associated with violence in the general population (e.g., substance use, hostility, psychopathy). Finally, persons with schizophrenia are more likely to be the victims of violent crimes than they are to perpetrate them.