Structural brain abnormalities in patients with bulimia nervosa.

Computed tomographic (CT) brain scans were performed in 50 inpatients with bulimia nervosa, 50 anorectic inpatients, and 50 age-matched control subjects. A number of patients with bulimia nervosa had enlarged ventricles and/or sulcal widening, but the degree and frequency of ventricular dilatation and sulcal widening were not so pronounced as in patients with anorexia nervosa. As the bulimic patients were of normal body weight, the CT abnormalities cannot be attributed to emaciation, which has often been suggested as the cause of abnormalities found in anorectic patients. Since many bulimic patients repeatedly attempt to lose weight by going on restrictive diets, the morphological brain alterations may reflect the endocrine and metabolic reactions to starvation--regardless of whether starvation has led to emaciation, as in the case of anorexia nervosa, or only counterbalanced the binges of high-caloric food. This assumption is supported by the finding that in both bulimic and anorectic patients ventricular size is inversely correlated with the plasma levels of triiodothyronine, a low concentration of which is an indicator for starvation.