The endocrinology of aging

Physiologic systems have substantial reserves in younger individuals. The p rocess of aging and intercurrent pathologic processes gradually eliminate t hese reserves. Changes in endocrine systems, including menopause in women, androgen deficiency in men, loss of skeletal mass, decrease in growth hormo ne serum concentrations, and increased incidence of type 2 diabetes are all more common or certain in older individuals. This review summarizes the pr ogression of each of these processes with age, the potential outcomes of th e untreated process, and the treatment outcomes for these age-related losse s. Maintenance of a premenopausal lipid profile presumably protects against cardiovascular events. Maintenance of skeletal mass reduces fracture risk and risk for loss of mobility and independence. Testosterone replacement in hypogonadal older men improves strength and presumably function and indepe ndence. Growth hormone therapy is reported to have similar effects. Improve ment of long-term outcomes in older type 2 diabetics, however, is more diff icult to demonstrate. (C) 1999 American Association for Clinical Chemistry.