Skeletal muscle mass by bioelectrical impedance analysis and calf circumference for sarcopenia diagnosis

Skeletal muscle mass (SMM) plays an important role in health and physical performance. Its estimation is critical for the early detection of sarcopenia, a disease with high prevalence and high health costs. While multiple methods exist for estimating this body component, anthropometry and bioelectrical impedance analysis (BIA) are the most widely available in low- to middle-income countries. This study aimed to determine the correlation between muscle mass, estimated by anthropometry through measurement of calf circumference (CC) and skeletal mass index (SMI) by BIA. This was a cross-sectional and observational study that included 213 functional adults over 65 years of age living in the community. Measurements of height, weight, CC, and SMM estimated by BIA were made after the informed consent was signed. 124 women mean age 69.6 ± 3.1 years and 86 men mean age 69.5 ± 2.9 years had the complete data and were included in the analysis. A significant positive moderate correlation among CC and SMI measured by BIA was found (Pearson r= 0.57 and 0.60 for women and men respectively (p=0.0001)). A moderate significant correlation was found between the estimation of SMM by CC and by BIA. This suggests that CC could be used as a marker of sarcopenia for older adults in settings in lower-middle-income countries where no other methods of diagnosing muscle mass are available. Although the CC is not the unique parameter to the diagnosis of sarcopenia, it could be a useful procedure in the clinic to identify patients at risk of sarcopenia.