Clinical and neuropsychological features of violence in schizophrenia: A prospective cohort study

The increased risk of violence in schizophrenia has been linked to several environmental, clinical and neuropsychological factors, including executive dysfunction. However, data about the nature of these effects are mixed and controversial. The main aim of this study was to investigate the relationship between clinical and neuropsychological factors with violence risk in patients with schizophrenia, taking into account current psychopathology and lifetime alcohol use. We compared a sample of patients living in Residential Facilities (RFs) with schizophrenia and a past history of interpersonal violence (vSZ, N=50) to patients with schizophrenia matched on age, gender and alcohol abuse/dependence but with no violence history (nvSZ, N=37). We then established the association between the clinical and neuropsychological factors that predicted violence over a 1year follow-up period. The results revealed that vSZ patients living in RFs were characterized by greater compulsory hospital admissions, higher anger and less negative symptoms as compared to nvSZ patients. vSZ patients performed better on executive and motor tasks than nvSZ; however, these differences appeared to be explained by the lower negative psychotic symptom in the vSZ group. Both groups were involved in episodes of violence during the follow-up period; among the two, the vSZ patients were more likely to be violent. Negative symptoms predicted less verbal aggression at 1year follow-up. Overall, these findings support a key role of negative rather than positive symptoms in driving violence risk among SZ patients living in RFs, in a manner that negative symptoms are linked to a lower risk of violence.