FOR THE PREVENTION OF POSTMENOPAUSAL OSTE OPOROSIS - HOW BENEFICIAL IS TRANSDERMAL HORMONE REPLACEMENT THERAPY

Question: Can osteoporosis and cardiovascular risk be effectively and simultaneously prevented with transdermal estradiol replacement therap y (in combination with norethisterone acetate 1 mg per day, oral, cycl ically for 12 days monthly)? Methods: A selected, representative group of healthy women with an average age of 52 years, with confirmed natu ral menopause for 1 to 4 years, randomly allocated to a treatment-grou p with hormone replacement (n = 42) and a control-group in = 70), with homogeneous main parameters in the two groups, can be compared, witho ut distortion of the findings, during the period of the two-year inter vention study: the purely trabecular bone mass in the distal radius wa s specifically measured, prospectively, with the highly accurate, thre e-dimensional, peripheral quantitative computed tomography (thin- und multi-layer technology; Densiscan 1000) and the serum lipid, lipoprote in and apolipoprotein levels were measured (at the end of the gestagen cycle) in the morning fasting state. Results: One-third of the person s of the control-group showed an annual loss of trabecular bone mass o f more than 3.5%. These fast-losers, who on the basis of the annual bo ne-destruction rates are to be classified in the upper tertiles of the two groups, suffered a loss of trabecular bone of 4.2+/-0.4% (mean+/- SEM) in the treatment-group, compared with 7.3+/-1.0% in the control-g roup in the first year; in the second year no loss of trabecular bone was observed in the treatment-group, while in the control-group the hi gh rate of trabecular-bone destruction continued unchanged. The slow-l osers (belonging to the middle and lower tertiles according to the bon e loss rates) showed equally little change in their trabecular bone ma ss after the menopause, which can be described as physiological, with mean yearly values between -1.1 and +0.4%, both in the treatment-group and in the control-group. Under the transdermal hormone replacement t herapy only the triglyceride and total cholesterol levels fell in comp arison with the control-group, but without any significant changes in the atherogenic index, either in regard to the LDL/HDL or apolipoprote ins B/A-I ratios. Conclusions: To be able to make valid statements it is necessary to study the effectiveness of a measure or of a preparati on for the prevention of osteoporosis in fast-losers, who are to be ra ndomized to the respective study-groups and whose status has been conf irmed by tests. Transdermal hormone replacement therapy - low estradio l dose in combination with NETA - stops the pathologically increased l oss of trabecular bone only in the second year of the treatment; the a ntiatherogenic effect, however, is not confirmed. Only an individually adjusted therapy based on test results, with follow-up control, can c onstitute an efficient, ethically justifiable postmenopausal prophylax is of both osteoporosis and coronary heart disease.