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

Abstract

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.

Keywords: Aggression; Impulsivity; Psychopathy; Schizophrenia; Trait aggressiveness.