Determinants of the first decade of bone loss after menopause at spine, hip and radius

This study documented bone loss at three different sites in the early postm enopausal period, and examined potential predictors. Forty-three women unde rwent repeated measurements of bone density at the lumbar spine, proximal f emur and distal radius for up to 14 years. Individual rates of bone loss we re calculated for the spine and hip; for radial trabecular bone, rates were calculated separately for two time periods, earlier and later after menopa use. In the spine and radius, initially high rates of loss diminished with time after menopause. No positive correlations for bone loss were found bet ween the three sites, suggesting that faster than average bone loss was spe cific to individual bones. High body mass index (BMI) was significantly pro tective against fast bone loss at the spine and radius; in the spine, each unit increase in BMI was associated with a similar to 5% reduction in the r ate of bone loss. Of the other variables measured (maximum oxygen consumpti on, lean body mass, fat mass, mean psoas muscle area at the L3 level, hand grip strength as well as anthropometry) only bone densitometry was sufficie ntly predictive to help guidance on hormone replacement or other prophylact ic therapy. The data suggest that the known relationship between excessive leanness and risk of osteoporosis and vertebral fracture after menopause mi ght in part be due to fast postmenopausal bone loss. Because bulk of psoas muscle was associated with low spine loss rates, the data also support a ro le for applied muscular loading in local maintenance of bone density.