BONE-MINERAL DENSITY AND HORMONE LEVELS IN MENOPAUSAL AUSTRALIAN WOMEN

To assess the relationships between bone mineral density (BMD) at the lumbar spine and femoral neck and menopausal status, age, physical var iables, and lifestyle and gynecological factors. BMD and follicle-stim ulating hormone (FSH), estradiol and inhibin levels were measured in 1 67 women born in Australia, aged 46-57 years, who had no record of rec eiving hormone replacement therapy. Using the premenopausal group as a baseline, the FSH level was higher in peri- and postmenopausal subjec ts (p < 0.0005), and estradiol and inhibin levels in the postmenopausa l women were lower (p < 0.0005). Mean (+/- SE) lumbar spine and femora l neck BMD were 15 +/- 3% and 10 +/- 3% lower, respectively, in postme nopausal than in premenopausal women. Lumbar spine BMD decreased with increasing age in perimenopausal women only (p < 0.005), and femoral n eck BMD decreased with increasing age in the pre-, peri- (p < 0.05) an d postmenopausal women. The difference between femoral neck BMD in the pre- and postmenopausal women was explained by the difference in age between these groups, whereas for lumbar spine BMD the menopausal stat us was an additional determining factor. There was a negative effect o f smoking on femoral neck BMD (p < 0.05) in postmenopausal women. In t he perimenopausal decade the femoral neck BMD is primarily dependent o n age, whereas lumbar spine BMD is dependent on both age and menopausa l status.