Psychopathological alterations and neuroimaging findings with discriminant value in eating behavior disorders.

Introduction: The difficulties encountered in regards to defining the diagnosis of patients with an Eating Behavior Disorder (EBD) have favored the use of multidimensional models. This study has aimed to identify which psychopathological and neurobiological variables could have a discriminating capacity regarding the different EBD diagnostic subtypes.

Methods: A total of 42 patients with an EBD diagnosis (11 Restrictive Anorexia (R-AN), 10 Purgative Anorexia (P-AN), 7 Non-purgative Bulimia (NP-BN), 14 Purgative Bulimia (P-BN)), according to DSM-IV criteria, were selected from those who came for treatment in the Ciudad Real General Hospital Eating Disorder Unit. Twelve healthy controls were also included. All of the subjects underwent a brain SPECT to measure regional cerebral blood flow (rCBF) in baseline situation (rest). A second one was performed after a visual neutral stimulus (sight of a calm sea) and another one after confronting them with their own corporal image, filmed two weeks before. A battery of questionnaires was administered to evaluate general and eating psychopathology.

Results: Patients with NP-BN showed less eating and general psychopathology. Furthermore, unlike patients with R-AN and P-BN, they did not experience an increase of the rCBF when confronted with their own body image. Discriminant variables were body dissatisfaction measured with the BSQ, BMI; BITE scores, ideal silhouette scores, and temporal right hyperactivation when they were shown their own body image.

Conclusions: The subgroup of patients diagnosed with NP-BN showed less emotional alteration and less emotional response when they were shown their own body image than the rest of patients with EBD. These differences might have implications from the therapeutic, prognostic or even taxonomic viewpoint.