Platelet serotonin content correlates inversely with life history of aggression in personality-disordered subjects

The objective of this study was to test the hypothesis that platelet serotonin (5-hydroxytryptamine, 5-HT) content is correlated with measures of aggression in healthy human subjects. Platelet 5-HT content (ng/mg protein) was measured in personality-disordered (PD) and normal control (NC) subjects. Aggression was assessed with the Life History of Aggression (LHA), the Buss–Durkee Hostility Inventory (BDHI), and the Motor Aggression and Research Criteria for Intermittent Explosive Disorder (IED-IR); impulsivity was assessed with the Eysenck Personality Questionnaire II (EPQII) and the Barratt Impulsiveness Scale (BIS-11). LHA Aggression, but not impulsivity, scores showed significant inverse correlations with platelet 5-HT content in all subjects or in PD subjects alone. The findings in PD subjects remained significant after co-varying for race. PD subjects with IED-IR had lower platelet 5-HT content compared with PD subjects who did not have IED-IR, although this finding only approached significance after controlling for race. This study demonstrates an association between reduced platelet 5-HT content and aggression in PD subjects. Similar to other studies of platelet 5-HT markers, these data suggest that platelet 5-HT content may also reflect central 5-HT alterations and may be used as a biological marker in appropriate patient samples. [Copyright &y& Elsevier]