Hypothalamic osteopenia--body weight and skeletal mass in the premenopausal woman.

Clearly, changes in skeletal bone mass are one of the major issues of potential clinical concern in the health care of the thin premenopausal woman. Each of the three parameters of skeletal mass--1) initial pubertal growth, 2) rate of bone loss, and 3) superimposed estrogen-deficient osteoporosis--may be negatively influenced by syndromes associated with low body weight and weight loss. Inherent in constitutional thinness and nutritional patterns of thin women are alterations in bone growth and rates of bone loss which may predispose to osteopenia and fracture in later adulthood. When these negative factors are compounded by hypothalamic/pituitary-mediated hypoestrogenism, decreased initial bone mass and true osteoporosis may result. We now possess excellent radiographic tools for monitoring bone mass but do not have the capability to predict fracture or diagnose osteoporosis. Urgently needed are longitudinal prospective studies of the dynamics of both trabecular and cortical bone growth and epidemiologic correlation as to the clinical impact (fractures) of decreased BMD in thin women. For the present, a physiologically oriented program directed toward prophylaxis--maximizing initial bone mass, decreasing rates of adult bone loss, and minimizing active osteoporosis--embracing early dietary calcium supplementation and hormonal therapy on an individually assessed basis seems most prudent. Indeed, this bodily "disease" of osteopenia may not be a pathologic process of bone metabolism at all, but truly an "ailment of the spiritual part"--secondary manifestations of sociologic and endocrinologic alterations inherent in the struggles of the mind and body to maintain low body weight.