Evaluating Diagnosis Strategy of Sarcopenia in Chinese Community Older People according to the 2019 Asian Working Group guideline: A Cross-Sectional Study

Abstract

Background Most diagnostic studies of sarcopenia in Asian areas follow the 2019 Asia Working Group for Sarcopenia (AWGS) guideline. The guideline proposed separated diagnosis strategies for community vs hospital for difficulty of measuring muscle mass in community settings. Evaluation the whole diagnosis process together with screening instruments in community preventive service setting is serious needed. Methods The study is a cross-sectional study. Questionnaire survey was done to evaluate SARC-F and SARC-CalF. Calf circumference(CC), Handgrip strength, gait speed and bioelectrical impedance analysis (BIA) were measured. Four scenarios about different diagnosis strategies were simulated, the sensitivity, specificity and AUC of ROC curve were calculated to evaluate the diagnostic accuracy. Results A total of 2453 participants were included. The sarcopenia prevalence was 14.1%, separately 15.4% and 13.1% for male and female. According to the diagnosis procedure of community, in case-finding stage, when using CC, SARC-CalF and SARC-F alone or combined three instruments, the sensitivities were separately 0.84,0.23,0.07 and 0.86, the specificities were separately 0.58,0.93,0.99 and 0.57, the AUCs of ROC curve were 0.710,0.581,0.530 and 0.717 respectively. Using CC and combined situations showed acceptable sensitivity and AUC, but SARC-F or SARC-CalF alone had missed most of sarcopenia. In assessment stage, handgrip strength test was added to those positive people in case-finding stage. the sensitivities were 0.61,0.17,0.06 and 0.63 respectively, the specificities were 0.92,0.98,0.99 and 0.92 respectively, the AUCs of ROC curve were 0.768,0.575,0.523 and 0.776. The sensitivity dropped quickly. In diagnosis stage, measurement of BIA and gait speed were added to those positive people in assessment stage, the sensitivities were 0.61,0.17,0.06 and 0.63, the specificities were all 1.00, the AUCs were 0.806,0.587,0.530 and 0.816. For CC, when cut-offs including critical value would extremely improve sensitivity and AUC of ROC curve. Conclusions Diagnosing sarcopenia in community, using SARC-F or SARC-CalF alone should not be recommended in case-finding stage, however, using CC and including critical value of cut-offs are more appropriate. In assessment stage, combined using muscle strength and physical performance rather than choosing one are recommended to avoid sharp reduce in sensitivity.