Hypothalamic pituitary adrenal function in patients with anorexia nervosa.

Hypothalamic pituitary adrenal function was studied in 14 patients with anorexia nervosa. Although basal plasma cortisol levels in the morning were elevated in most cases, basal plasma ACTH levels were not suppressed. Oral administration of 1 mg dexamethasone 10 hr before blood sampling failed to suppress plasma ACTH and cortisol levels in most patients with anorexia nervosa. Apparent biological half-life of exogenous cortisol was prolonged in all 4 patients with anorexia nervosa tested. The cortisol response to insulin-induced hypoglycemia and exogenous ACTH appeared to be blunted in these patients. It is concluded that anorexia nervosa has dysfunctions of hypothalamic pituitary adrenal axis, especially an abnormal feedback mechanism on ACTH secretion.