Differences of cortical 5-HT2A receptor binding index with SPECT in subtypes of anorexia nervosa : Relationship with personality traits?

Objective Using single photon emission computed tomography and the 5-HT 2A receptor antagonist, 123 I-5-I-R91150, we explored differences in 5-HT 2A binding index in anorexia nervosa patients with and without bulimic features. We also searched for associations between temperament dimensions and cortical 5-HT 2A binding. Method About 9 restrictive and 7 bulimic anorexia nervosa patients were examined and cortical 123 I-5-I-R91150 binding index values were compared between the two subgroups. Open explorative correlation analysis was used to examine any relationships between binding index values and temperament scores, as assessed with the Temperament and Character Inventory. Results 5-HT 2A binding index was significantly reduced in the parietal cortex in bulimic anorexia nervosa patients in comparison with restrictive anorectics. Further, a positive correlation was documented between reward dependence and parietal 5-HT 2A binding index across patients in the two subgroups. Discussion Restrictive anorexia nervosa patients differ from binging/purging anorexia nervosa patients on the basis of a reduced parietal 5-HT 2A binding index in the latter. We speculate that the finding of a positive correlation between parietal 5-HT 2A binding and reward dependence might reflect an association between these two variables, at least in anorexia nervosa patients.