Distinctive profiles of traits predisposing to violence in schizophrenia and in the general population.

OBJECTIVE

We delineated important trait predispositions to violence, including psychopathic and impulsive traits and trait aggression, in patients with schizophrenia and in the general population.

METHOD

The study included 144 subjects: 40 violent (VS's) and 34 nonviolent (NV's) patients with schizophrenia, 35 healthy controls (HC's) and 35 non-psychotic violent subjects (NPV's). We used the Psychopathy Checklist, Buss-Perry Aggression Questionnaire, and Barratt Impulsiveness Scale (BIS-11). Life History of Aggression, psychiatric symptoms, drug/alcohol abuse and history of conduct problems were also assessed.

RESULTS

The two violent groups presented with more severe psychopathy, trait aggressiveness and impulsivity than the non-violent subjects; some of these traits being more pronounced in NPV's than in VS's. We further divided the violent patients (VS's) into 2 subgroups, those with a history of conduct problems (VS-CD) and those without (VS-NCD). When we compared these 2 subgroups to each other and to NPV's, we obtained 3 distinct multivariate profiles of traits, consisting of psychopathic traits, anger, motor impulsiveness, and self-control problems. NPV's have the profile with the most severe impairments, followed by VS-CD's and then VS-NCD's. Psychiatric symptoms were more strongly associated with violence in VS-NCD's than in VS-CD's.

CONCLUSION

Our study provides new insights on trait predispositions to violence. Trait aggressiveness, psychopathic and impulsive traits form a distinctive profile which underlies a core predisposition to violence across populations, including patients with schizophrenia, but particularly in those with a history of early conduct problems. In those without such problems, the symptoms of the illness play a more important role for the violent behavior.