VERTEBRAL POSTMENOPAUSAL BONE LOSS IS REDUCED IN OVERWEIGHT WOMEN - ALONGITUDINAL-STUDY IN 155 EARLY POSTMENOPAUSAL WOMEN

To study the influence of excess body weight on vertebral postmenopaus al bone loss, 155 healthy early postmenopausal women were divided into 2 groups according to their body mass index (BMI = weight/height2) an d prospectively followed over a mean 31-month period. Spinal (L2-L4) b one mineral density was measured by dual photon absorptiometry. The an nual rate of vertebral bone loss (percentage) was significantly reduce d (-0.54 +/- 1.1% vs -1.46 +/- 1.6%; P < 0.05) in the overweight group (BMI, greater-than-or-equal-to 25; n = 40) compared to that in the no rmal weight group (BMI, <25; n = 115). At baseline, a significant decr ease in the urinary calcium/creatinine ratio was observed in the overw eight group, which suggested a decrease in bone turnover. A significan t correlation was between the annual rate of bone loss and the BMI (r = 0.21: P < 0.05), but not the body weight. The positive correlation b etween vertrebral postmenopausal rate of bone loss and BMI was confirm ed after adjustment for age and time since menopause. Moreover, plasma dehydroepiandrosterone sulfate levels were higher in the high BMI gro up than in the normal BMI group (P < 0.05). We conclude that within th e first year, after menopause, moderate excess body weight significant ly reduces vertebral postmenopausal bone loss. This effect is probably related to excess adipose tissue through increased conversion of estr ogen from adrenal precursors and/or increased production of adrenal an drogens.