Use of Conventional Regional DXA Scans for Estimating Whole Body Composition

Background: Using soft-tissue composition in-conventional regional dual-energy X-ray absorptiometry (DXA) scans of the spine and hip to predict whole body composition (whole-body fat mass, whole-body lean mass and trunk-fat-mass)instead of a whole body DXA scan. Methods: We identified 143 adult patients who underwent DXA evaluation of the whole body. Anthropometric indices were also measured. Datasets were split randomly into two parts; the derivation set including a sample of 100 subjects and the validation set including a sample of 43 subjects. Multiple regression analysis with the backward stepwise elimination procedure was used for the derivation set and the estimates-were then compared with the actual measurements from the whole-body scans for the validation set. The-R-a(2) (adjusted, coefficient of multiple determination) and SSE (error sum of squares) criteria Were applied to compare-regression models. Results: Using-Multiple linear regression analyses, the best equation for predicting whole-body fat mats (R-a(2)=0. 946) included gender, height, weight, Waist circumference (WC), spine fat fraction and hip fat fraction; the best equation for predicting whole-body lean mass (R-a(2)= 0. 970) included gender, weight, WC, spine fat fraction and hip fat fraction; and the best equation for predicting trunk-fat mass (R-a(2)= 0 944) included gender, Weight, spine fat fraction and hip fat fraction. Conclusion: The results of this study show that regional DXA scant of the spine and hip can be used to accurately predict body composition.