The development of functional hypothalamic amenorrhea (FHA) in weight-stable, nonathletic women has long been thought to be psychogenic in origin. This study was designed to gain insight into the possibility that nutritional deficits and compensatory endocrine-metabolic adaptations contribute to the development and maintenance of FHA of the psychogenic type. Nutritional intake, insulin sensitivity, and 24-h dynamics of insulin/glucose, cortisol, leptin, somatotropic, and LH axes were

more »

... sly assessed in eight women with FHA not associated with exercise or weight loss and in eight age-and body mass index-matched regular cycling controls (NC). The percent fat body mass was lower and lean body mass was higher in FHA than in NC (P Ͻ 0.05). The FHA subjects scored higher (P Ͻ 0.05) on two Eating Disorder Inventory subscales and had a higher (P Ͻ 0.05) Beck depression rating than NC, although all were in the subclinical range. Although daily caloric intake did not differ, FHA consumed 50% less (P Ͻ 0.001) fat, twice (P Ͻ 0.05) as much fiber, and more carbohydrate (P Ͻ 0.05) compared to NC. During the feeding phase of the day, FHA exhibited lower glucose (P Ͻ 0.05) and insulin (P Ͻ 0.01) levels than NC, and the degree of hypoinsulinemia was directly related to relative dietary fat (r ϭ 0.73). Although 24-h mean GH levels did not differ, the pattern of GH release in FHA was distinctly altered from that in NC. GH pulse amplitude was blunted, pulse frequency was accelerated 40% (P Ͻ 0.01), and interpulse GH concentrations were elevated 2-fold (P Ͻ 0.01) throughout the day for FHA compared to NC. This distorted pattern of GH pulses was associated with a 40% decrease (P Ͻ 0.01) in GH-binding protein levels. Levels of the insulin-dependent insulinlike growth factor (IGF)-binding protein-1 (IGFBP-1) were elevated (P Ͻ 0.001) during the feeding portion of the day in FHA and were