Childhood Abuse and Platelet Tritiated-Paroxetine Binding in Bulimia Nervosa: Implications of Borderline Personality Disorder

Background: Co-occurrence of bulimia nervosa andborderline personality disorder has been attributed to sharedfactors, including childhood abuse and disturbances in centralserotonin (5-hydroxytryptamine; 5-HT) mechanisms. To explore thisnotion, we conducted a controlled assessment of childhood abuseand 5-HT function in bulimics with and without borderlinepersonality disorder.

Method: Forty patients with bulimia nervosa, confirmed with the Eating Disorders Examination interview (14 with borderline personality disorder and 26 without), and 25 normal-eater controls were assessed for clinical symptoms (eating disturbances, mood lability, impulsivity, and dissociation) and childhood sexual and physical abuse. We also conducted tests of platelet tritiated-paroxetine binding in blood samples from 27 of the bulimics (11 with borderline personality disorder and 16 without) and 16 of the controls.

Results: Relative to normal eaters, bulimicsshowed greater affective instability, overall impulsivity, and ahistory of physical abuse. However, borderline bulimics aloneshowed elevated motor impulsivity, dissociation, and rates ofsexual abuse. Paroxetine-binding tests indicated no differencesattributable to comorbid borderline personality disorder, insteadlinking bulimia nervosa with or without borderline personalitydisorder to substantially reduced 5-HT transporter density.

Conclusion: Results suggest relativelyautonomous pathologic entities: one, relevant to bulimia nervosa,being associated with abnormal 5-HT transporter function andaffective instability, but relatively independent of childhoodsexual abuse; another, relevant to borderline personalitydisorder, onto which sexual abuse, dissociative symptoms, andbehavioral impulsivity converge. We propose that abnormal 5-HTfunction may, however, constitute one basis for the frequentco-occurrence of bulimic and borderline disturbances.