Enhancing SARC-F: Improving Sarcopenia Screening in the Clinical Practice

Abstract

Objectives: To validate the (Brazilian) Portuguese-translated version of the SARC-F questionnaire and to verify its performance in the separate sarcopenia screening and muscle function evaluation contexts. In addition, by associating SARC-F to an anthropometric measurement (as an estimate of muscle mass), to test for improvements in its sarcopenia screening efficacy.

Design: Cross-sectional study.

Setting: Urban population of Pelotas, a middle-sized city in Southern Brazil.

Participants: Subsample of 179 community-dwelling elderly aged 60 years or older derived from a population-based study (COMO VAI?).

Measurements: Sarcopenia was evaluated using the European Working Group on Sarcopenia in Older People's diagnostic criteria: dual-energy X-ray absorptiometry, handgrip strength, and walking speed test. Participants also completed SARC-F and their calf circumference (CC) was measured. SARC-F and CC were combined into an original score. The questionnaires' performances were evaluated through receiver operating characteristic curves, sensitivity/specificity analyses, and Pearson χ².

Results: Sarcopenia was identified in 15 (8.4%) participants by the European Working Group on Sarcopenia in Older People's criteria. Areas under the receiver operating characteristic curves of SARC-F were 0.592 (95% confidence interval (CI) 0.445, 0.739) screening for sarcopenia and 0.779 (95% CI 0.710, 0.846) evaluating muscle function (P < .001). The SARC-F+CC association significantly improved SARC-F's sarcopenia screening performance [area under the curve: 0.736 (95% CI 0.575, 0.897); comparing with SARC-F alone: P = .027]. A substantial improvement in sensitivity was achieved without compromising the remaining parameters.

Conclusions: Despite the satisfactory performance evaluating muscle function, SARC-F alone has not achieved adequate results as a sarcopenia screening tool. However, the SARC-F+CC association significantly improved SARC-F's sarcopenia screening performance, enabling its use in the clinical practice.

Keywords: Sarcopenia; body composition; calf circumference; muscle mass; screening; validation study.