Aggressive behaviour in schizophrenia: role of state versus trait factors.

The objective of this article was to elucidate the relative importance of state vs. trait factors in determining aggressive behaviour in schizophrenia. Thirty-one aggressive schizophrenia patients in rehabilitation wards were compared with 31 matched non-aggressive patients with respect to their psychopathology, phenomenologies of hallucinations and delusions, neuroleptic motor side effects, history of aggression and personality traits. Significant differences between the two groups were found in relation to psychopathology, affective responses to hallucinations/delusions, history of aggression and personality traits, but there were no significant differences regarding neuroleptic motor side effects. The effects of history of aggression as well as personality traits were independent of and similar to the total level of psychopathology, but were much smaller when compared to those of negative affective responses to hallucinations/delusions.