EFFECT OF EARLY MENOPAUSE DUE TO OVARIECTOMY ON BONE LOSS

Objectives: Early menopause is a well-known risk factor for osteoporos is. It could be an aggravating factor when induced ovariectomy. This s tudy was conducted to compare vertebral bone density and biochemical m arkers of bone remodelling in patients with spontaneous and induced ea rly and ''normal'' menopause. Methods: The main biochemical markers of bone remodelling (serum calcium, albumin, alkaline phosphatase, osteo calcin and urinary calcium/creatinine) together with bone density (L2 - IA) were measured in 55 women (age 46-77 at inclusion) with spontane ous (n = 16) or surgically induced (n = 39) early menopause (before ag e 40) and in 227 women (age at inclusion 47-67 years) with normal meno pause (after 40 years) either spontaneous (n = 136) or surgically indu ced (n = 91). Results: At equivalent ages, vertebral bone density was 7 to 12% lower (p < 0.05) in women with early menopause than in women menopaused after 40. However, the serum levels of alkaline phosphatase and osteocalcin as well as the Nordin index were similar in the two g roups. After adjusting for the duration of menopause, women with early menopause did not have a higher bone density than their ''normal'' me nopause conterparts despite their younger age (9 years younger). No di fferences were observed between spontaneous and surgically induced men opause. Conclusion: These results suggest that bone loss is more rapid or more long lasting after precocious menopause. Surgically induced m enopause does not appear to aggravate bone loss independently of age. Effective prevention of this hormone dependent bone loss is required.