Osteoporosis CMAJ 1997;156:1530 See response by: D.A. Hanley and R.G. Josse In the article "Effects of ovarian hormone therapy on skeletal and extraskeletal tissues in women" (CMAJ 1996;155[suppl]:929-34 [full text]), Dr. Robert G. Josse states that "the risk of osteoporotic fractures of both wrist and hip is reduced by 50% to 60% in women who begin estrogen therapy within the first 3 years of menopause and who continue therapy for 6 to 9 years." Two references are given, one from a 1980 article and the other from a 1981 article. According to the recent literature, prevention of osteoporosis and fractures through estrogen therapy depends not only on starting therapy within 5 years of menopause but continuing it indefinitely. For example, Felson, Zhang and Hannan[1] reported that "in the women less than 75 years of age who had taken estrogen for seven or more years, the bone density was, averaging all sites, 11.2% greater than in women who had never received estrogen. Among women 75 years of age and older in whom the duration of therapy was comparable, bone density was only 3.2% higher than in women who had never taken estrogen." The view that hormone replacement therapy for fracture prevention must be started shortly after menopause and continued indefinitely is supported by a 1995 report by Cauley and associates for the Study of Osteoporotic Fractures Research Group.[2] The important findings of this prospective cohort study were that hip and wrist fractures were significantly reduced in women who had started taking estrogen replacement therapy within 5 years of menopause and who did not discontinue it. Estrogen given in combination with a progestin was just as effective as estrogen alone and protected current smokers as well as nonsmokers. By contrast, there was no significant protection among current users who had started hormone replacement therapy more than 5 years after menopause, or among women who had started hormone replacement therapy shortly after menopause, continued taking it for many years, but were no longer current users.[2] Ettinger and Grady's[3] conclusion from reviewing the literature was that "to provide maximal protection, estrogen treatment may have to be started at the time of menopause and never stopped." What explains the discrepancy between Josse's conclusions and those of these other authors? Have I misread the literature? Is the recent literature wrong? Or are proponents of hormone replacement therapy unwilling to state that these drugs have to be taken for life because many women would be unwilling to undertake a lifelong program? Kenneth G. Marshall, MD Department of Family Medicine University of Western Ontario London, Ont. References Felson DT, Zhang Y, Hannan MT. The effect of postmenopausal estrogen therapy on bone density in elderly women. N Engl J Med 1993;329:1141-6. Cauley JA, Seeley DG, Ensrud K, Ettinger B, Black D, Cummings SR, for the Study of Osteoporotic Fractures Research Group. Estrogen replacement therapy and fractures in older women. Ann Intern Med 1995;122:9-16. Ettinger B, Grady D. The waning effect of postmenopausal estrogen therapy on osteoporosis. N Engl J Med 1993;329:1192-3. Send a letter to the editor responding to this letter Envoyez une lettre à la rédaction au sujet de cette lettre | CMAJ June 1, 1997 (vol 156, no 11) / JAMC le 1er juin 1997 (vol 156, no 11) |