Prevalence and definition of sarcopenia in community dwelling older people Data from the Berlin aging study II (BASE-II)

Sarcopenia describes the age-associated loss of muscle mass, strength and function. The aim of this study was to compare the prevalence of sarcopenia in a cohort of community dwelling elderly people living in Berlin, Germany, according to the criteria proposed by current consensus statements and to study the respective impact on self-reported physical performance. This study included 1405 participants from the Berlin aging study II (BASE-II). The appendicular skeletal muscle mass index (SMI) was assessed with dual energy X-ray absorptiometry (DXA), muscle strength was measured by hand grip strength and the timed up and go" test (TUG) was performed as a functional parameter to reflect mobility. The prevalence of sarcopenia was 24.3 % in terms of reduced SMI only and considerably lower for sarcopenia with reduced grip strength (4.1 %) and sarcopenia with limited mobility (2.4 %). Only 0.6 % of the participants fulfilled all three criteria. Of the subjects with a normal SMI, 8.6 % had reduced grip strength and 5.1 % had limited mobility, whereas 1.3 % subjects fulfilled both criteria. Participants with reduced strength or function reported severe difficulties in performing physical tasks significantly more often than participants with normal or reduced SMI alone (p < 0.029-p < 0.0001). In BASE-II low skeletal muscle mass was much more frequent than reduced grip strength or poor function. Reduced strength and function were found to be associated with a greater impact on physical performance than reduced muscle mass. Low SMI does not seem to be a prerequisite for low strength or limitations in mobility.