Longitudinal study of bone loss in pre- and perimenopausal women: Evidencefor bone loss in perimenopausal women

Bone loss before and around the time of menopause is not well characterized by longitudinal studies. We measured bone mineral density at various skele tal sites - total body, femoral neck, trochanter, anteroposterior (AP) and lateral spine, and forearm with dual-energy X-ray absorptiometry in a large prospective cohort of 272 untreated pre- and perimenopausal women aged 31- 59 years, at I year intervals for 3 years. Sex steroids and the following m arkers of bone remodeling were measured: serum osteocalcin (OC), procollage n I carboxyterminal extension peptide, bone alkaline phosphatase (BAP) and urinary crosslinks (CTX and NTX). Seventy-six women were classified as peri menopausal and 196 as premenopausal, Over the 3 years, premenopausal women had no significant bone loss at any site and a small but significant increa se in bone mineral density at the trochanter, total hip, AP spine and radiu s. Perimenopausal women significantly lost bone from cancellous and cortica l sites, i.e,, the femoral neck, trochanter and lumbar spine. In perimenopa usal women with increased follicle stimulating hormone, the rate of bone lo ss at the femoral neck correlated negatively with OC and BAP. In perimenopa usal women, serum estradiol levels decreased during the 3 years of follow-u p and bone loss from the trochanter and the AP spine was correlated with se rum estradiol after 3 years. In conclusion, among premenopausal women there is no bone loss. In contrast, there is a rapid and diffuse bone loss in pe rimenopausal women, related to decreased estrogen secretion. Bone markers m ay be useful to identify these women losing bone.