Lack of Efficacy of Psychological and Pharmacological Treatments of Eating Disorders: Neurobiological Background

Background. Treatments of eating disorders result too often in partial psychological and physical remission, chronic course, dropout, relapse and death, with no fully known explanations for this failure. In order to clarify this problem, we conducted a three branches study to identify the biochemical background of cognitive-behavioral psychotherapy (CBT), individual psychology brief psychotherapy (IBPP), and psychotherapy-pharmacotherapy with CBT+olanzapine in anorexics (AN) and bulimics (BN) by measuring the levels of plasma homovanillic acid (HVA) for dopamine secretion, plasma 3-methoxy-4-hydroxy-phenylglycol (MHPG) for noradrenalin secretion, and platelet [3 Hydrogen]-Paroxetine-binding Bmax and Kd for serotonin transporter function. The data were then compared with psychopathological and physical alterations. Methods. Branch 1 investigated the effects of 4 months of CBT on plasma HVA, MHPG and [3 Hydrogen]-Par-binding in 14 AN-restricted, 14 AN-bingeing/purging, and 22 BN inpatients. Branch 2 investigated the effects of 4 months of IBPP on plasma HVA in 15 AN and 17 BN outpatients. Branch 3 investigated the effect of 3 months of CBT+olanzapine (5 mg/day) in 30 AN outpatients. The data are analyzed using one-way ANOVA for repeated measures for the changes between basal and post-treatment biological and psychological parameters, two-way ANOVA for repeated measures for the differences in the psychobiological data in the 3 groups, Spearman's test for the correlations between basal and final changes in the psychological and biological scores.