Start with muscle mass or muscle strength in diagnosis and management of sarcopenia? A systematic review of guidance documents.

BACKGROUND AND OBJECTIVES: Sarcopenia has garnered extensive attention in clinical practice since its high prevalence and significant impact on clinical outcomes. Multiple organizations have published guidance documents on sarcopenia, offering evidence-based recommendations for clinical practice and/or research. We aimed to appraise the methodological quality of the included documents and synthesize available recommendations for the screening, diagnosis, and intervention of sarcopenia. METHODS AND STUDY DESIGN: We conducted a search on PubMed, Embase, Scopus, Cochrane Library, China National Knowledge Infrastructure, guideline database, and guideline organizations and professional societies websites for clinical practices, consensus statements and position papers in terms of sarcopenia, muscle atrophy or muscle loss published before April 17, 2023. The AGREE II instrument was used by three independent reviewers to assess the methodological quality of these documents. RESULTS: Thirty-six guidance documents published between 2010 and 2023 were included. Seven documents fulfilled ≥ 50% of all the AGREE II domains. Seven underwent a Delphi process and six graded the strength of the recommendations. The process of screening (n=21), early diagnosis of sarcopenia (n=12), diagnosis of sarcopenia and severe sarcopenia (n=10), and management (n=21) were increasingly recommended. SARC-F (n=14) was the most recommended screening tool, and the assessment of muscle function was considered the first step in diagnosing sarcopenia. The management strategy for both age-related and disease-related sarcopenia mainly focused on exercise and nutrition intervention. CONCLUSIONS: The guidance documents have provided referential recommendations that have great guiding significance. But the inconsistency in recommendations and variation in methodological rigour suggests that high-quality evidence is lacking yet.

Validity of the modified versions of SARC-F+EBM for sarcopenia screening and diagnosis in China: the PPLSS study.

BACKGROUND AND OBJECTIVES: It is recommended by Asian Working Group for Sarcopenia to early identify people at risk for sarcopenia using simple screening tools like SARC-F. The modified version SARC-F+EBM showed higher diagnostic performance. However, this cut-off value of body mass index (BMI) remained uncertain to be used in Chinese population. In this study, we used appropriate BMI recommended for Chinese older population and further modified SARC-F+EBM by combining calf circumference. METHODS AND STUDY DESIGN: Diagnostic tests were performed and the receiver operating characteristics analyses were conducted between the SARC-F, SARC-F+EBM (cut-off of BMI: ≤ 21 kg/m2), SARC-F+EBM (CN) (cut-off of BMI: ≤ 22 kg/m2), SARC-CalF and SARC-CalF+EBM (CN) (cut-off of BMI: ≤ 22 kg/m2) in 1660 community-dwelling participants aged ≥ 65 years from China. RESULTS: The participants had an average age of 71.7±5.1 years, of which 56.8% were women. All the modified models could enhance the areas under the receiver operating characteristic curve (AUC) of original SARC-F (all p<0.001). The SARC-F+EBM (CN) also showed a significantly higher sensitivity of 47.4% (p<0.001) and an AUC of 0.809 (p=0.005) than SARC-F+EBM. SARC-CalF+EBM (CN) was validated to be of great diagnostic value of the highest AUC of 0.88 among these sarcopenia screening tools, including SARC-F, SARC-CalF and SARC-F+EBM (CN) (all p<0.001). Using this study population as a reference, the optimal cut-off value of SARC-CalF+EBM (CN) is ≥12 points, with a sensitivity of 79.3% and a specificity of 80.7%. CONCLUSIONS: The SARC-F+EBM (CN) and SARC-CalF+EBM (CN) could enhance the diagnostic performance of SARC-F and SARC-F+EBM and are suitable sarcopenia screening tools for Chinese population.