The possible role of estrogens and progestagens in the prevention of osteoporosis

Abstract

The multifactorial disease of osteoporosis is one of the most frequent diseases, affecting about 5 - 6 Mio. postmenopausal women in Germany, today. In spite of the introduction of new technologies of fracture risk assessment and new pharmacological opportunities the incidence of fracture is still increasing. Therefore, early identification of women at high risk as well as early and individualised preventive measures are essential in the prevention of osteoporosis. Changes of dietary habits as well as lifestyle including an increase in physical activity are of up most importance. In addition to Calcium and Vitamin D supplementation, hormone replacement therapy (HRT) is accepted as the first line and cost effective pharmacological treatment for the prevention of osteoporosis. Numerous cross sectional, case-control and prospective studies showing the effect of HRT on bone reabsorption and bone mineral density (BMD) have been published. HRT reduces bone turnover which is followed by an increase of BMD. A number of case-control and cohort studies as well as a few recent prospective studies have been investigating the effect of HRT on osteoporosis related fracture. These studies confirm that HRT leads to a significant decrease of osteoporosis related fracture (Hip fracture by > 25 %). However, randomised, prospective studies are needed to underline the effect on osteoporosis related fracture. Although the effect of HRT on BMD is independent of both, the age at which treatment is started and the route of administration, a dose-response relation as well as a greater response in patients with a lower initial BMD has been reported. Since bone is lost rapidly when treatment is stopped, the duration of treatment is clinically important in evaluating the effect of HRT on BMD. Hereby, a duration of 10 years and more seems desirable. Since the ongoing controversial discussion on the duration dependent increase of the incidence of breast cancer and the discussion on secondary prevention of cardiovascular disease, any therapy decision must be individually evaluated. The following article gives a systematical review on the recent literature regarding the influence of HRT on BMD and osteoporosis related fracture.