Analysis of Electrical Bioimpedance for the Diagnosis of Sarcopenia and Estimation of Its Prevalence

Sarcopenia in older adults has become a public health problem associated with several adverse health outcomes that lead to high costs of care. This is why an accurate and timely identification of this condition is required, in order to carry out prevention and early intervention to reduce its prevalence. The most important components of sarcopenia are the loss of quantity and quality of skeletal muscle and diagnosis begins with the evaluation of these two dimensions. Whilst in developed countries there are cumbersome and expensive methods to assess the amount of muscle, such as dual energy x-ray absorptiometry (DEXA), magnetic resonance imaging (MRI) and computerized tomography (CT) countries with fewer resources are able to take advantage of less expensive and easy to apply techniques for the diagnosis of sarcopenia, such as the analysis of electrical bioimpedance. In this study, the latter method was used to estimate the amount of muscle mass, in conjunction with the assessment of the grip strength of the hand and the short battery of physical performance, in order to estimate the prevalence of sarcopenia in 210 older adults in Manizales, Colombia. For this, cut-off points obtained from <2 SDs of muscle mass of a young adult population in the same city were used. The results determined a prevalence of 11.4%, a figure that differs from that found in the same population when skeletal mass index (SMI) cutting points obtained from a Taiwanese or a Mexican American population were used (9.5% and 27.6%). On the other hand, the phase angle, another bioimpedanciometric parameter, emerges which could be a promising risk marker for sarcopenia, since the difference in this between individuals with or without sarcopenia was significant (5.79 ± 0.76 vs. 6.26 ± 0.79, p = 0.006°). However, as was shown in the analysis of the ROC curve, its predictive capacity was low in this study and an additional exploration of this topic is required.