Humberto Nicolini

Temperament and character in violent schizophrenic patients

UNLABELLED Preliminary evidence shows that personality traits are important in determining violent behavior in schizophrenia. As only some patients with schizophrenia show a greater risk for violence, this risk may therefore be considered as dynamic, varying as a function of the extent to which certain personality dimensions are present and the degree to which environmental events moderate or exacerbate their expression. OBJECTIVE To compare temperament and character dimensions between violent and non-violent schizophrenic patients and to determine which temperament and character dimensions are predictors of violent behavior in schizophrenia. METHOD We recruited 102 schizophrenic patients without concomitant substance abuse 4 months prior to the assessment. Diagnoses were based on the SCID-I. Personality dimensions were assessed with the Temperament and Character Inventory and violent behaviors with the Overt Aggression Scale. RESULTS Higher levels of the temperament dimension novelty seeking and a lower cooperativeness, as a character dimension, were risk factors for violent behavior in schizophrenic patients. DISCUSSION Our data indicate that schizophrenic patients will show a greater risk for violence according to certain personality configurations and the degree to which environmental events moderate or exacerbate their expression.

Dopamine D4 Receptor (DRD4) Gene Polymorphism in the First Psychotic Episode

BACKGROUND Dopamine D4 receptor (DRD4) has shown some interesting properties at genetic and possibly functional levels. It has been suggested that some molecular variants of the DRD4 gene (e.g., four and seven alleles) could be implicated in the pathogenesis of psychotic disorders. Additionally, the VNTR polymorphism could be implicated in part of the response to treatment with neuroleptics. This study tested the possible association between the 48-bp tandem repeats in exon 3 of the DRD4 gene and patients experiencing their first psychotic episode. METHODS Patients with a first psychotic episode (FPE, n = 37) were diagnosed and compared with a matched control group (n = 37). The FPE group was subdivided into two categories: those with nonaffective and those with affective psychoses. The variable number of tandem repeats (VNTR) region of the DRD4 gene was amplified by PCR procedures. Chi-square statistics and appropriate corrections and adjustments were used for data analysis. CONCLUSIONS A significantly lower frequency of the four repeat (4-R) carriers in the FPE group was observed. This association was sustained mainly by the affective psychotic group (chi2 = 9.99 df = 2, p = 0.0073). Although these results require testing with stringent methods, it is suggested that the DRD4-4R allele may confer some protection against psychosis, mainly of the affective subtype.