DXA Versus Multifrequency BIA In College-aged And Elderly Individuals: An Update

Body composition assessment is an important clinical and research tool. Dual energy x-ray absorptiometry (DXA) is the ‘gold standard’ and valuable in the research environment, however, it is expensive to obtain, reliant on a trained technician, requires a large, dedicated space, and needs annual service. Bioimpedance spectroscopy (BIS) measurements have improved with the application of quad-polar multifrequency units and may offer a quick and portable alternative at a fraction of the cost compared to DXA. PURPOSE: To compare measurements of bone mineral content (BMC), fat mass, and lean body mass (LBM) obtained with BIS compared to those obtained with DXA. METHODS: 99 (69 female) individuals (36 from abstract #4135 in 2024) [avg (range) = 32 ± 21 (18-97) yr; 168 ± 9 (151-193) cm; 70 ± 13 (47-98) kg; 29 ± 8 (11-47) %fat] had their BIA and DXA whole body composition measured within minutes of each other. Three compartments were compared between BIS and DXA: BMC, fat mass, and LBM. Pearson’s correlation coefficients were determined. RESULTS: There are strong positive correlations for all variables between the assessment METHODS: BMC (r = 0.87), fat mass (r = 0.96), and lean mass (r = 0.98). CONCLUSION: A quadripolar multifrequency BIS device can be a body composition surrogate in research environments over a broad range of ages and body sizes if a DXA machine is impractical to use.