Background: Aging presents changes in muscle mass that may lead to sarcopenia. Identifying safe, quick, and accessible methods to assess muscle mass is imperative.
Aims: The purpose of this investigation was to compare the assessments of appendicular skeletal muscle mass (ASMM), fat-free mass (FFM), and fat mass (FM) between bioelectrical impedance analysis (BIA) and dual-energy X-ray absorptiometry (DXA).
Methods: Seventy-three healthy, community-dwelling, physically active males (n = 19) and females (n = 54) (BMI = 27.1 ± 4.3 kg m-2) between the ages of 55-85 years underwent total-body BIA and DXA. ASMM was estimated via BIA from a previously published regression equation while DXA ASMM was calculated as the sum of the measured total arm lean mass and total leg lean mass. Paired-samples t tests with a significance level of p < 0.05 were conducted, while agreement between the methods was assessed via Bland-Altman plots.
Results: In comparison to DXA, the chosen BIA equation overestimated ASMM (21.61 ± 5.82 kg vs. 18.82 ± 4.81 kg) and FFM (49.57 ± 9.94 kg vs. 46.22 ± 10.11 kg) and underestimated FM (24.59 ± 8.28 kg vs. 27.13 ± 10.01 kg), all p < 0.001. Visual inspection of the Bland-Altman plots revealed wide limits of agreement. Female participants were more clustered around the mean than male participants.
Discussion: The multifrequency BIA device and chosen ASMM estimation equation resulted in wide limits of agreement and significantly different comparisons to the reference method of DXA.
Conclusion: Future research should continue to investigate and validate methodologies to screen older individuals for characteristics of aging-related diseases, such as sarcopenia.
Keywords: Aging; Body composition; Fat mass; Fat-free mass; Imaging.
© 2021. The Author(s), under exclusive licence to Springer Nature Switzerland AG.