Endocrine dysfunction in anorexia nervosa and bulimia: comparison with abnormalities in other psychiatric disorders and disturbances due to metabolic factors.

The eating disorders of anorexia nervosa and bulimia are associated with marked disturbances in endocrine function. Studies of the hypothalamic-pituitary-adrenal,-thyroid, and -ovarian axes are reviewed, in order to ascertain whether and to what extent alteration in endocrine response is the consequence of abnormal eating, or whether the endocrine abnormalities are primary. Many, if not all, of the disturbances which have been documented can be accounted for the metabolic consequences of disturbed eating behavior, including especially the effects of weight loss. However, it is possible that primary hypothalamic dysfunction may account for or contribute to the following abnormalities: hypercortisolism, blunted TSH response to TRH, and hypogonadism. Given the possibility that primary hypothalamic disturbances are present, the specificity of these disturbances with respect to eating disorders as opposed to other psychiatric disorders, is investigated. It is concluded that, with the possible exception of alterations in the hypothalamic-pituitary-ovarian axis, such disturbances appear not to be specific to eating disorders; rather, they are also present in other psychiatric disorders. In particular, the data reviewed are consistent with the hypothesis that the eating disorders have psychobiological features in common with major affective disorder.