Lean tissue index measured with bioimpedance (BIA) and strength and physical performance tests associated with sarcopenia in a hemodialysis population

Abstract

Sarcopenia, loss of muscle mass, is one of the components of the protein energy wasting (PEW) and frailty often associated with chronic kidney disease. The European Working Group on Sarcopenia in Older People (EWGSOP) proposed a definition of sarcopenia based on three criteria: low muscle strength, low physical performance and documentation of low muscle mass.The Body Composition Monitor (BCM Fresenius) is an apparatus, which can analyze the body composition through multifrequency bioimpedance spectroscopy and yields a lean tissue index (LTI) and a fat tissue index (FTI) expressed in Kg/m2. Both indexes have been validated using DEXA as the reference method. Normal values, adjusted by age and sex, have been described for the normal population. Some studies on chronic kidney disease consider anomalous values those below percentile 10 of the normal population. Other studies evaluate patients’ clinical evolution according to whether their indexes are higher or lower than the median value of the involved population.