Evaluation of a Leg-to-Leg Bioimpedance Device in the Estimation of Abdominal Visceral Fat for the Elderly – Comparison with CT

Background: This study aimed to assess the accuracy of the standing leg-to-leg bioelectrical impedance analyzer (LBIA) for estimating abdominal visceral fat with body mass index (BMI) scores ranging from non-overweight to obese in elderly Chinese individuals. Methods: The abdominal visceral fat area (VFA) at the lumbar level of L4-L5 was measured for 100 elderly (age 68.5 ± 8.5 years) individuals using LBIA and computed tomography (CT) (respectively represented as VFALBIA and VFACT). The VFA from LBIA were compared with those from CT under various BMI levels. Results: The average BMI of the subjects was 24.3 ± 4.1 kg/m2 (58 non-overweight individuals had BMIs < 25 kg/m2, and 42 overweight individuals had BMIs ≥ 25 kg/m2). The correlation coefficient (r) of VFALBIA and VFACT was r = 0.707 with a standard estimate of error (SEE) = 21.96 cm2, and the limit of agreement (LOA) was in the range of −67.46 to 58.48 cm2. The r value for non-overweight and overweight was 0.707 (p < 0.001) and 0.356 (p < 0.001), SEE was 21.36 cm2 and 20.42 cm2 with LOA values ranged between −68.40 to 46.00 cm2 and −61.79 to 71.19 cm2. Conclusion: The LBIA results showed that each obese group all has large LOA when compared with the CT reference values. The study suggests that the LBIA accuracy for estimating VFA is limited in the Chinese elderly population