Bone mineral density correlates strongly with basal metabolic rate in postmenopausal women.

BACKGROUND

This study investigated the relationships of bone mineral density (BMD) with body composition, basal metabolic rate (BMR), and fat distribution.

METHODS

We measured body mass index (BMI), anthropometrics, and BMD in 345 postmenopausal women and 224 elderly men. Total body fat (TBF), fat distribution, and BMR were assessed using a body composition analyzer. Lumbar spine and proximal femur BMDs were measured with dual-energy X-ray absorptiometry.

RESULTS

Lumbar spine BMD was more strongly correlated with BMR (r=0.51, p<0.01) than with lean body mass (r=0.39, p<0.01) and waist hip ratio (r=-0.28, p<0.01) in postmenopausal women. The mean values of BMR in osteoporotic women were significantly lower than those for non-osteoporotic women (p<0.01). The prevalences of osteoporosis at the sites of lumbar spine and proximal femur were 32.1% and 23.3% in the women with BMR<1230 kcal, which were significantly higher than those of osteoporosis (5.4% and 7.7%) at the corresponding sites in the women with BMR> or =1230 kcal (p<0.01). In elderly men, the incidence of osteoporosis at the proximal femur was 29.5% in the subjects with BMR<1390 kcal, significantly higher than that (2.2%) in the subjects with BMR> or =1390 kcal (p<0.01).

CONCLUSION

BMR is more closely associated with bone density in elderly persons, at least as compared to TBF, BMI, or lean body mass.