EFFECT OF MENOPAUSE ON VERTEBRAL BONE MAS S - A LONGITUDINAL-STUDY

Objectives: We evaluated bone loss in women during the peri and post-m enopausal period in order to determine the exact effect of menopause o n vertebral bone density and biochemical markers of bone remodelling. Methods: One hundred fifty-seven women who consulted for menopause and who did not wish to receive substitution therapy were enrolled. Menop ause was defined as amenorrhoea greater than or equal to 1 year and se rum 17-beta oestradiol less than or equal to 20 pg/ml and luteinizing hormone > 30 IU/ml. Precocious or surgical menopauses were excluded. T wo groups were formed according to the hormone pattern: a peri-menopau sal group (n = 32, mean age 51.2 +/- 2.9 years) and a post-menopausal group (n = 125, mean age 54.3 +/- 3.7, menopause 1 to 11 years at entr y). Bone density was measured by biphonotonic absorptiometry and blood chemistry was performed with routine laboratory methods. All tests we re repeated at successive consultations and mean follow-up was 32 +/- 12 months.Results: Annual rate of bone loss was during peri-menopause (- 1.8 +/- 1.7%) and the first 1 years of menopause (- 1.6 +/- 1.6%), then decreased significantly beyond 4 years. Mean bone loss from 5 to 10 years menopause (- 0.60 +/- 1%). Initial serum calcium, phosphorus, alkaline phosphatase and osteocalcine levels were significantly highe r during post-menopause than during peri-menopause (p < 0.05). The uri nary calcium/creatinine ratio was comparable between the two periods a nd decrease after 4 years of menopause. Conclusion: This longitudinal study indicated that increased vertebral bone loss begins early during peri-menopause and is temporary since it does not continue beyond 5 y ears. It is important to consider these findings when developing strat egy for the prevention of menopausal osteoporosis.