Serum cholesterol and impulsive aggressive behavior in personality disorder patients
摘要
Low or reduced serum cholesterol has been associated with impulsive and aggressive behaviors. Diminished central serotonergic activity, as reflected by prolactin response to fenfluramine, has been associated with impulsive aggression in patients with personality disorders (Coccaro et al 1989). The present study explores the relationship between serum cholesterol and measures of impulsive and aggressive behaviors in patients with personality disorders. Seventy-two personality-disorder (PD) patients with or without borderline personality disorder (BPD, DSM-III), (39 males, age 44.1 ± 12.3: 9 BPD, 30 OPD and 33 females, age 38.6±12.7; 13 BPD, 20 OPD) were examined for evidence of irritability and aggression by self-report as measured by the Buss-Durkee Hostility Inventory (BDHI), and for evidence of impulsivity by self-report as measured by the Barratt Impulsivity Scale. Central serotonergic activity was measured by the prolactin response to fenfluramine challenge. Serum cholesterol was measured as part of initial medical screening by standard enzymatic assay. There was a positive correlation between serum cholesterol levels and age (r=0.33, p<0.01). Therefore, all analyses we performed controlling for age. An ANCOVA was performed with factors gender and borderline diagnosis with age as a covariate. There was a significant effect for diagnosis, with borderline patients having lower cholesterol levels (174.9±34.1) than non-borderline patients (209.7±40.9; F[1,67]=6.03, p<0.02). Female patients also demonstrated reduced cholesterol levels (183.4 ± 38.3) compared to male patients (212.3 ± 40.7; F[1,67]=3.98, p<0.05). There was no significant interaction effect between gender and diagnosis. Controlling for age, there was no statistically significant correlation between cholesterol levels and prolactin response to fenfluramine (r0.23, n=36, p=ns) and measures of impulsivity as measured by the BDHI; however, for women there was an inverse correlation between cholesterol and the Barratt Impulsivity scale (r0.43, n=33, p<0.05), for men the correlation was positive not for the total score but for the motor subscale of the Barratt (r=0.41, n=39, p<0.04). This study provides preliminary evidence that in a subpopulation of personality disordered patients with borderline personality disorder, serum cholesterol may be lower than in normals. There is no evidence to support a relationship between low serum cholesterol and aggression or impulsivity in this personality disordered population, nor is there evidence to support an association between low serum cholesterol and reduced central serotonin activity as measured by prolactin.