Comparison of the performance of five screening methods for sarcopenia

Background Sarcopenia leads to serious adverse health consequences. There is a dearth of screening tools for this condition, and performances of these instruments have rarely been evaluated. Our aim was to compare the performance of five screening tools for identifying elders at risk of sarcopenia against five diagnostic definitions. Subjects and methods We gathered cross-sectional data of elders from the SarcoPhAge ("Sarco"penia and "Ph"ysical Impairment with Advancing "Age") study. Lean mass was measured with X-ray absorptiometry, muscle strength with a dynamometer and physical performance with the Short Physical Performance Battery (SPPB) test. Performances of screening methods were described using sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and area under the curve (AUC), according to five diagnostic definitions of sarcopenia. For each screening tool, optimal cutoff points were computed using two methods. Results A total of 306 subjects (74.8±5.9 years, 59.5% women) were included. The prevalence of sarcopenia varied from 5.7% to 16.7% depending on the definition. The best sensitivity (up to 100%) and the best NPV (up to 99.1%) were obtained with the screening test of Ishii et al, regardless of the definition applied. The highest AUC (up to 0.914) was also demonstrated by the instrument of Ishii et al. The most specific tool was the algorithm of the European Working Group on Sarcopenia in Older People (EWGSOP; up to 91.1%). All NPVs were above 87.0%, and all PPVs were below 51.0%. New cutoffs related to each screening instrument were also proposed to better discriminate sarcopenic individuals from non-sarcopenic individuals. Conclusion Screening instruments for sarcopenia can be relevantly used in clinical practice to make sure to identify individuals who do not suffer from the syndrome. The screening test of Ishii et al showed better properties in terms of distinguishing those at risk of sarcopenia from those who were not at risk.