Diagnostic performance of SARC-F, SARC-CalF, and calf circumference for sarcopenia in middle-aged patients with cardiovascular disease

Background Declines in muscle strength and mass become increasingly apparent during middle age. Accordingly, the Asian Working Group for Sarcopenia (AWGS) 2025 consensus expanded the target population for sarcopenia assessment to include middle-aged adults (50–64 years). Early detection and intervention for sarcopenia are clinically important, particularly in patients with chronic conditions such as cardiovascular disease (CVD). However, the discrimination of widely used screening tools (SARC-F, SARC-CalF, and calf circumference [CC]) for sarcopenia in middle-aged patients with CVD remains unclear. Purpose This study aimed to clarify the diagnostic performance of SARC-F, SARC-CalF, and CC for sarcopenia defined by AWGS 2025 in middle-aged patients with CVD. Methods This was a retrospective cross-sectional study. We included patients aged 50–64 years admitted for acute CVD treatment. SARC-F and CC were assessed before hospital discharge. We also calculated the SARC-CalF, which combines SARC-F with CC. Sarcopenia was diagnosed according to AWGS 2025, newly defined sex-specific cutoff values of low handgrip strength and low skeletal muscle mass in individuals aged 50–64 years. To evaluate the identification of each screening tool for sarcopenia, we analysed the receiver operating characteristic (ROC) curves and the area under the curve (AUC). In addition, sex-stratified ROC analyses were performed to compare diagnostic performance between men and women. Results A total of 398 patients were included in the analysis, of whom 310 (77.9%) were men. The median body mass index was 23.5 (21.0–26.1) kg/m2. According to the AWGS 2025 criteria, sarcopenia was diagnosed in 140 (35.2%) patients. Among screening tools, SARC-CalF and CC demonstrated comparable discrimination for sarcopenia and both showed higher AUCs than SARC-F (AUC: SARC-F 0.654, SARC-CalF 0.808, CC 0.822; Figure 1). Furthermore, even after stratification by sex, both SARC-CalF and CC maintained high discrimination, with higher AUCs shown in women (Figure 2). Conclusions SARC-CalF and CC demonstrated high discrimination for sarcopenia defined by AWGS 2025 in middle-aged patients with CVD. Screening tools, including CC, particularly contribute to identifying sarcopenia in this population, suggesting that they should be prioritized in the clinical setting.