Association Of Body Composition With Bone Mineral Density: A Study In5888Men And Women

ObjectiveUsing dual-energy X-ray absorptiometry (DXA), we measured bone mineral density(BMD) and body composition, and fat distribution in men and women of different ages. Thestudy aims to investigate the associations of body composition and fat distribution with BMDin men and women of different ages.Methods5888men and women aged20to95years were analyzed. The male subjects was dividedinto young group (age﹤50y, n=793) and older group (age≥50y,n=958), and the femalesubjects was divided into premenopausal group (n=1551) and postmenopausal group (n=2586). The BMD of the whole body (WB), lumbar spine, femur neck, total hip, and wholebody and regional body composition(lean mass, LM and fat mass, FM) were measured byDXA. Fat distribution was assessed by DXA-based trunk FM and appendicular FM. Pearsoncorrelation and multiple linear regression analysis were performed to examine theassociations of BMD with body composition and fat distribution.ResultsThe peak BMD values of the whole body, spine, femur neck and total hip were observedin men aged20to29years, respectively, in women aged30to39years at all sites. Wholebody FM increased with age was due to the increase of the central trunk FM in men, wholebody LM decreased with age was due to the reduction of the peripheral limbs LM. Aftermenopause, whole body FM increased was due to increase of both the central trunk FM andthe peripheral limbs FM in women, whole body LM was not obviously decreased, however,peripheral limbs LM decreased obviously.In Pearson correlation, both WBLM and WBFM were positively associated with BMDof all sites in all groups (all P﹤0.05). In multiple linear regression analysis, both WBLM andWBFM had a positive contribution to BMD at all sites. WBLM was the greater contributor toBMD of all sites in young men; WBLM was the greater contributor to BMD of all sites inolder men, except the lumbar spine; WBLM was the greater contributor to BMD of all sites inpremenopausal women; however, WBFM was the greater contributor to BMD of all sites in postmenopausal women.In multiple linear regression analysis, Trunk FM was an independent and positivecontributor to BMD of all sites in all groups even additionally adjusting for LM, however,appendicular FM was a negative or no significant contributor to BMD.ConclusionsThis study suggests that both WBLM and WBFM were positively related to BMD.WBLM was the greater contributor to BMD in men and premenopausal women, however,WBFM was the greater contributor to BMD in postmenopausal women.