Background: Reduced central serotonergic neurotransmission has been demonstrated in individuals with excessive alcohol consumption and/or alcohol dependence. Childhood maltreatment has also been found to have a negative impact on central serotonergic neurotransmission. The aim of this study was to evaluate the impact of childhood maltreatment on central serotonergic dysfunction in alcohol-dependent individuals.

Methods: Adult men with a diagnosis of alcohol dependence (n=18) were recruited from outpatient treatment units for alcoholism. Central serotonergic neurotransmission was assessed by a neuroendocrine method, that is, the prolactin (PRL) response to the selective 5-HT reuptake inhibitor citalopram. Childhood maltreatment was assessed retrospectively by the Childhood Trauma Questionnaire.

Results: Alcohol-dependent individuals with childhood experience of emotional abuse had significantly lower PRL response compared with those without such abuse (3 +/- 5 and 64 +/- 24mU/l, respectively; t=6.51, p<0.001). Among those who reported childhood emotional abuse, 4 of 7 individuals had flat PRL responses in comparison with none in those with no report of such abuse (p<0.01).

Conclusions: This is the first study to show that self-reported childhood maltreatment, in particular emotional abuse, in male alcohol-dependent individuals is associated with a quite dramatic (more than 90%) reduction in central serotonergic neurotransmission. It should, however, be noted that the number of individuals is relatively small, and the results should therefore be considered as preliminary.