Violence and duration of untreated psychosis in first-episode patients.

BACKGROUND: Violent behaviour can be a presenting sign of first-episode psychosis. Duration of untreated psychosis (DUP) has been a focus of attention because it is a potentially modifiable factor that may influence outcome. AIMS: The aim was to review the literature addressing the following issues: prevalence of violence or aggression in the first episode of psychosis, violence or aggression during the periods before and after the initiation of treatment, the DUP and relation between DUP and the level of violence or aggression in first-episode psychosis.
METHODS: MEDLINE and PubMed databases were searched for articles using the combination of key words 'aggression' (limited to humans) and 'first episode' and 'psychosis'.
RESULTS: Available evidence suggests that the prevalence of violent behaviour in the first episode of psychosis, particularly schizophrenia, is greater than during the later stages of the illness. First-episode psychosis is associated with an increased risk of homicide. There is some limited support for an effect of DUP length on serious violence or aggression. Violent behaviour frequently develops before the onset of first episode. Substance use disorders are additional factors that elevate the risk for violence in these patients.
CONCLUSIONS: Earlier treatment of first episode psychosis might prevent some homicides. Personality factors and substance abuse may be more important than psychotic symptoms in the development of aggressive behaviour in patients with first-episode psychosis.