Relationship of temperament and behaviour measures to the prolactin response to fenfluramine in depressed men

Abstract 

Low central nervous systems (CNS) serotonin has been linked to aggression, impulsivity and disinhibition in both animal and human studies. Low cerebrospinal fluid (CSF) 5-hydroxindoleacetic acid (5HIAA) has been reported in violent criminals, arsonists and violent suicide attempters. Reduced prolactin response to fenfluramine has been found in aggressive patients and criminal offenders. Cloninger's dimension of harm avoidance is hypothesised to be related to CNS serotonin levels, but studies have reported contradictory results. Forty-eight men with major depression received a fenfluramine challenge as well as a number of measures of temperament and behaviour: the Tridimensional Personality Questionnaire (TPQ); the Eysenck Personality Questionnaire (EPQ); the Barratt Impulsivity Scale (BIS); the Hopkins Symptom Checklist (SCL-90); and clinician-rated personality disorder symptoms. The prolactin response to fenfluramine was not related to EPQ or TPQ measures except the TPQ dimension of reward dependence and the EPQ Lie scale. The prolactin response to fenfluramine was not related to BIS measures or to SCL-90 measures except the SCL-90 somatization scale. The prolactin response to fenfluramine was not related to personality disorder diagnoses or to a measure of repeated self-harm. Thus, in a sample of moderately depressed male outpatients, there was very little relationship between personality, behavioural measures and the prolactin response to fenfluramine. We suggest that alterations in serotonin functioning, when measured using the prolactin response to fenfluramine, may be more commonly linked to behavioural abnormalities in personality-disordered or criminal samples.

Keywords:  Impulsivity, Harm avoidance, Repeated self-harm, Borderline personality disorder, Depression