Defining optimal anthropometric thresholds for sarcopenia screening in community-dwelling older Vietnamese adults

Abstract Sarcopenia poses a growing health challenge for Vietnam’s aging population, yet effective screening remains limited by impractical standard diagnostics and a lack of validated, population-specific anthropometric thresholds. We conducted a cross-sectional study of 416 community-dwelling adults aged ≥60 years in Can Tho, Vietnam, to establish optimal cutoff values for body mass index (BMI), calf circumference (CC), arm circumference (AC), and waist circumference (WC) against the Asian Working Group for Sarcopenia 2019 (AWGS 2019) criteria. Receiver operating characteristic (ROC) analysis in R (pROC package) identified optimal cutoffs by maximizing the Youden index (sensitivity + specificity − 1): BMI ≤ 22.6 kg/m2 for men and ≤ 21.2 kg/m2 for women; CC ≤ 34.5 cm/32.0 cm; AC ≤ 26.0 cm/24.0 cm; and WC ≤ 85.0 cm/78.0 cm. Applying these Vietnam-specific thresholds improved the area under the curve from 0.75 to 0.77 for BMI, 0.61 to 0.70 for AC, 0.64 to 0.68 for CC, and 0.57 to 0.69 for WC, while specificity increased by 14–60% depending on the index. The Vietnam-specific BMI cutoff provided the best overall diagnostic accuracy; CC and AC were less effective in women, likely reflecting sex-specific differences in muscle mass and fat distribution, whereas WC achieved high specificity in women but lower overall accuracy, indicating potential utility of alternative measures such as the weight-adjusted waist index (WWI). These findings support the adoption of Vietnam-specific BMI thresholds as a simple, cost-effective primary screening tool for sarcopenia in older adults, with CC, AC, and WC as viable alternatives when BMI cannot be obtained. Implementing population-specific anthropometric cutoffs in national screening programs may facilitate earlier detection of sarcopenia, optimize resource allocation, and inform future research on combined indicator strategies. Competing Interest Statement The authors have declared that no competing interests exist Funding Statement Yes Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Not Applicable The details of the IRB/oversight body that provided approval or exemption for the research described are given below: This study is part of the ViSarco Project, a multi-phase research initiative aimed at improving sarcopenia screening strategies in Vietnam. This institution-based original study received ethical approval from the Ethics Committee in Human Research of Walailak University on 24 July 2024, under approval number WUEC-24-263-01. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Not Applicable I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Not Applicable I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Not Applicable Data Availability All relevant data are within the manuscript and its Supporting Information files