Low serotonin and dopamine metabolite concentrations in cerebrospinal fluid from bulimic patients with frequent binge episodes.

Cerebrospinal fluid neurotransmitter metabolite levels were studied to assess whether measures of central serotonin, dopamine, or norepinephrine function are associated with severity of abnormal eating patterns in patients with bulimia nervosa. In comparison with healthy controls (N = 17), hospitalized bulimic patients with a history of binge eating more frequently than twice daily (N = 11) had significantly lower CSF concentrations of 5-hydroxyindoleacetic acid and homovanillic acid. For the total patient group (N = 29), levels of both metabolites were significantly inversely correlated with binge frequency. On the basis of preclinical studies, these results were examined in the context of speculative models in which low central serotonin function might contribute to blunted satiety responses in bulimic patients, while low central dopamine activity might play a role in abnormal hedonic responses to food.