Accuracy Of Multifrequency BIA Measurements Compared To DXA In African American Cancer Survivors

Body composition assessment is an important clinical and research tool. Dual energy x-ray absorptiometry (DXA) is the ‘gold standard’ and useful in the research environment, however, it is expensive, reliant on a trained technician, requires a large space, and is immoveable. Bioelectrical impedance analysis (BIA) measurements have improved with the application of quadripolar multifrequency equipment and could offer a faster, cheaper, and portable alternative if measurements are comparable. PURPOSE: To determine how well bone mineral content (BMC), lean body mass (LBM), and fat mass measurements made with BIA compared to those made with DXA. METHODS: 106 fasted African American prostate cancer survivors [45-81 yr, 56.4-171.0 kg, 162-199 cm, 17-42% fat] had their BIA and DXA whole body composition assessed between May 2019 and Dec 2022 as part of a larger study. Measurements were taken within minutes of each other. The study is longitudinal, so some men had up to 4 measurements within a year. Three compartments [BMC, fat mass, and LBM] were compared between BIA and DXA. Pearson’s correlation coefficients were determined. RESULTS: 232 DXA v BIA pairs were taken in the timeframe. Absolute fat mass (r=0.94) and lean mass (r=0.93) were highly correlated between the assessment methods, although bone mineral content was poorly correlated (r=0.43). CONCLUSIONS: Lean and fat mass taken with BIA can be a reliable body composition surrogate to DXA for research purposes if bone mineral content is not a criterion variable of interest. This technology could be used in the field to assess weight loss and changes in muscle in cancer survivors.