The optimal cut-off value of five-time chair stand test for assessing sarcopenia among Chinese community-dwelling older adults

Background The five-time chair stand test (5CST) as an indicator of muscle strength and physical function is the first step in assessing sarcopenia. We aimed to determine the optimal cut-off value of the 5CST for assessing older adults with sarcopenia in the Chinese community. Methods We used a stratified cluster random sampling method to recruit older adults from Chinese communities. The handgrip strength was assessed using an electronic handgrip dynamometer. The 5CST and gait speed were assessed by the trained researchers. The bioimpedance analysis device was used to evaluate the skeletal muscle index. We used the Asian Working Group for Sarcopenia diagnosis criteria as the gold standard. According to the receiver operating characteristic curve, we determine the optimal cut-off value using the Youden index. Results A total of 1027 participants were included in this analysis, including 337 men and 690 women with an average age of 70.35 +/- 7.24 years. The prevalence of sarcopenia in total participants was 24.9%. The optimal cut-off value of 5CST in the total population was 10.9 s. Stratified by age and gender, for the older adults aged 60-69 years, the optimal cut-off values were 9.8 s in men and 10.2 s in women; for the older adults aged 70-79 years, cut-off values were 10.2 s in men and 10.9 s in women; and for the older adults over 80 years, cut-off values were 14.0 s in men and 11.5 s in women (all P < 0.001). The areas under the curve of 5CST were 0.632 in men and 0.650 in women (both P < 0.001). Using the newly defined cut-off values, the prevalence of sarcopenia increased significantly (P < 0.001). Conclusions We determined the optimal cut-off value of the 5CST for assessing older adults with sarcopenia in the Chinese community, and this cut-off can significantly improve the detection rate of sarcopenia. The cut-off determined in our study will help community workers detect more people with sarcopenia and benefit from early intervention and management of sarcopenia in practice.