Validation of bioelectrical impedance analysis in the evaluation of body composition in patients with breast cancer.

ABSTRACT

BACKGROUND: The evaluation of body composition is an essential parameter for preventing obesity and sarcopenic obesity, which are prognostic factors in breast cancer. This study aims to validate the bioelectrical impedance analysis (BIA) of women who are breast cancer survivors by using the dual-energy x-ray absorptiometry (DXA) measurement method. METHODS: This validation study included 104 women without metastasis between 32 and 72 years old (mean 47.03 ± 8.59) whose treatment was completed 6 months prior. Body composition analysis was performed sequentially using both measurements and when participants were hungry. RESULTS: Meaningful differences were found in fat-free mass (FFM) (BIA 46.57 ± 5.54 kg; DXA 41.06 ± 5.11 kg), body fat percentage (%BF) (BIA 34.28% ± 6.24%; DXA 43.91% ± 5.58%), body fat mass (FM) (BIA 25.37 ± 8.84 kg; DXA 31.24 ± 9.09 kg), and lean soft tissue mass (LSTM) (BIA 4.42 ± 5.66 kg; DXA 38.75 ± 4.98 kg) (P < 0.001). Powerful associations for body FM and strong associations for other parameters were seen. A constant and/or proportional error was found between the two devices within the direction of strong and solid components. Compared with DXA, the BIA measurement gives a lower estimate of %BF and FM and a higher estimate of LSTM and FFM. CONCLUSIONS: By the mathematical relationship between the two measurement methods, it seems possible to adapt the body composition parameters obtained from BIA of patients with breast cancer to DXA results. In the future, there will be a need to evaluate these two devices with more extensive studies.