ASSOCIATIONS OF BODY-FAT DISTRIBUTION, CIRCULATING SEX-HORMONES, AND BONE-DENSITY IN POSTMENOPAUSAL WOMEN

The associations of body fat distribution, sex hormone levels, and bon e mineral density (BMD) were examined in 52 postmenopausal Caucasian w omen. Body fat distribution was assessed by waist to hip ratio (WHR) a nd abdominal fat weight (between the iliac crest and L1), as determine d by dual energy x-ray absorptiometry. Bone mineral densities were det ermined by dual energy x-ray absorptiometry, and total estradiol, tota l testosterone, and sex hormone-binding globulin (SHBG) levels were de termined by RIA. Subjects taking hormone replacement had significantly greater total estradiol and SHBG concentrations and a lower free andr ogen index. BMDs tended to be higher in subjects taking estrogen repla cement after adjustment for body weight. There was no difference betwe en subjects taking hormone replacement or not taking hormone replaceme nt in WHR or abdominal fat weight. Subjects with a gynoid (lower body) distribution of body fat had higher SHBG concentrations than subjects with a more android (upper body) distribution of body fat. Subjects w ith an android distribution of body fat had greater BMDs than subjects with a gynoid distribution of body fat. Abdominal fat weight and WHR were significant predictors in regression models for all BMD parameter s. The results of this study suggest that there is an association betw een body fat distribution and BMD, with the android distribution havin g higher BMDs.