The age-related loss of muscle mass and/or strength and performance, sarcopenia, has been associated with geriatric syndromes, morbidity and mortality. Although sarcopenia has been researched for many years, currently there is a lack of consensus on its definition. Some studies define sarcopenia as low muscle mass alone, whereas other studies have recently combined low muscle mass, strength and physical performance suggested by the European Working Group on Sarcopenia in Older People, as well as the Asian Working Group for Sarcopenia. The arbitrary use of various available sarcopenia definitions within the literature can cause discrepancies in the prevalence and associated risk factors. The application of population-specific cut-off values in any sample population can be problematic, particularly among different ethnicities. Using commonly used cut-off points to define sarcopenia, including solely muscle mass and combined definitions, on a community-dwelling elderly Japanese population, the prevalence of sarcopenia ranged from 2.5 to 28.0% in men and 2.3 to 11.7% in women, with muscle mass measured by dual-energy X-ray absorptiometry, and 7.1-98.0% in men and 19.8-88.0% in women measured by bioelectrical impedance analysis. Body mass index was the most prominent related factor for sarcopenia across the definitions in this Japanese sample. However, other associated hematological and chronic condition factors varied depending on the definition.
Keywords: muscle strength; sarcopenia; skeletal muscle mass; walking ability.
© 2016 Japan Geriatrics Society.