Applicability and agreement of different diagnostic criteria for sarcopenia estimation in the elderly

The purpose of this study cross-sectional study comprising 132 community dwelling elderly (≥ 60 years) was to identify sarcopenia prevalence in the Brazilian elderly, utilizing different diagnostic criteria and analyze agreement between criteria. Sarcopenia was assessed by nine muscle mass diagnostic criteria, by two muscle strength criteria and also by the combination of criteria. Prevalence was analyzed for each method, along with differences by gender and age group through calculation of the prevalence ratio (PR) and confidence interval (CI) 95%. The Kappa coefficient was used to analyze the level of agreement between all criteria. Sarcopenia prevalence varied between 60.6% and 8.3% with the application of muscle mass criteria, and between 54.2% and 48.8% with the application of strength criteria. The combination muscle mass+strength resulted in a decrease of prevalence in all criteria, varying between 36.6% and 6.1%. There was an increase in prevalence according to age groups for all methods. Prevalence was higher for men according to three muscle mass criteria, and higher in women for strength criteria and by two combined mass+strength criteria. The best level of agreement was obtained for two methods that utilized dual energy X-ray absorptiometry (DXA). The prevalence of sarcopenia differs by gender and age and definition criteria. The low agreement levels obtained between methods and the different prevalence values encountered indicate the necessities of an operational definition for the estimation of sarcopenia in different population.