Sex steroids and bone mass. A study of changes about the time of menopause.

TLDR

To investigate how sex steroids influence bone loss, 84 peri‑ and postmenopausal women were followed every four months for three years. At each visit, researchers measured midshaft and distal radius bone mass, sex steroids, gonadotropins, and bone gla protein. Bone loss averaged about 1 % per year in late perimenopausal and postmenopausal women but was negligible in early perimenopausal women, and both serum estrogen and bone gla protein levels predicted loss rates, with estrogen remaining a strong independent predictor even after accounting for bone gla protein, suggesting that part of estrogen’s effect is mediated through bone remodeling.

Abstract

To examine the relationships between bone loss and sex steroids, 84 peri- and postmenopausal women were studied at 4-mo intervals for 3 yr. At each visit, measurements were made of bone mass at the midshaft and distal radius, of steroids, of gonadotropins, and of bone gla protein (BGP). Bone loss was approximately 1% per yr among late perimenopausal and postmenopausal groups, whereas the early perimenopausal group lost no bone. Mean serum estrogen and BGP concentrations predicted rates of bone loss. BGP was negatively correlated with the rate of bone loss (r = -0.45) and with mean estrogen concentrations (r = -0.40). Multivariate regressions showed estrogen concentrations to be strong independent predictors of the slope of bone mass over time. When BGP concentrations were added to the models, the significance of estrogen was reduced, suggesting that a portion of the estrogen effect was mediated through effects on rates of bone remodelling.