Hormonal replacement therapy and the skeletal system.

The two most important risk factors for maintaining skeletal health are the bone mass obtained at skeletal maturity (peak bone mass) and the subsequent bone loss. Those women with a low peak bone mass and a rapid bone loss are thus at increased risk of developing osteoporosis in the future, and should be identified. This may be accomplished by determination of the bone mass combined with an estimate of the rate of the postmenopausal bone loss. The bone mass can be accurately assessed in the forearm by single photon absorptiometry. The postmenopausal bone loss can be estimated by three or four biochemical markers of bone turnover. The women at highest risk of developing osteoporosis should be offered preventive therapy, e.g., hormonal replacement therapy (HRT). HRT arrests the bone loss not only in early, but also in elderly postmenopausal women. The effect lasts as long as the therapy is continued. Several epidemiological studies have demonstrated that HRT decreases the number of osteoporotic fractures.