The state of research in anorexia nervosa and bulimia.

Recent studies suggest that some of the DSM III criteria for anorexia nervosa require revision. In particular exclusion for onset beyond 25, and a requirement for 25 per cent weight loss appear inappropriate, whereas amenorrhoea correlates better with anorectic psychology than weight. Although an increased incidence of affective disturbance among the relatives of anorectics and bulimics has been shown, the precise relationship with affective disorder remains unclear. Cortisol non-suppression and low MHPG excretion are related to weight loss. However, some areas of hypothalamic dysfunction cannot be explained by emaciation or diet. Pre-pubertal LH secretion patterns, absence of estrogen positive feedback on LH, and failure of LH response to clomiphene can persist despite normalisation of weight. Furthermore 1-dopa fails to induce the normal growth hormone response in weight restored anorectics, suggesting impairment at post-synaptic dopamine receptors. Body image studies have been varied, suggesting heterogeneity of body image distortion among anorectic subgroups. The role of family environment in the pathogenesis of anorexia nervosa has not been fully elucidated, although such a role in the relationship between bulimic symptomatology and personality disturbance have been suggested. Of the behavioral therapies, operant positive reinforcement that restores weight in a hospital setting has had the best results. Successful pharmacological approaches have included cyproheptadine (a serotonin antagonist), chlorpromazine and metoclopramide.