PLATELET SEROTONIN, MONOAMINE-OXIDASE ACTIVITY, AND [H-3]PAROXETINE BINDING RELATED TO IMPULSIVE SUICIDE ATTEMPTS AND BORDERLINE PERSONALITY-DISORDER

Background: The aim of the present study was to examine the relationsh ip between suicidal behavior and impulsiveness, and more generally bor derline personality disorder on the one hand, and platelet indicators of central serotonergic function on the other. Methods: After a suicid e attempt platelet serotonergic measures were obtained from 144 patien ts with at least one previous attempt. A major DSM-III-R Axis I diagno sis and the use of antidepressants were reasons for exclusion. Results : Platelet monoamine oxidase (MAO) activity was negatively correlated with the personality traits ''multi-impulsive behavior'' and ''disinhi bition.'' In accordance, platelet MAO activity was also lower in patie nts with less-planned suicide attempts. Platelet serotonin (5-HT) and recidivism were positively correlated with borderline personality diso rder, in particular chronic feelings of emptiness. Platelet 5-HT was l ower in patients with alcohol abuse. The maximum number of binding sit es (B-max) for paroxetine binding was positively correlated with ''sen sation seeking.'' Conclusions: These findings support the hypothesis t hat serotonergic involvement in impulsive suicidal behavior is mediate d by the relationship between serotonergic function and impulsiveness as personality trait. Other borderline personality traits relevant to recurrent suicidal behavior, in particular chronic feelings of emptine ss, appear also related to serotonergic measures. (C) 1998 Society of Biological Psychiatry.