Handgrip strength and muscle mass cutoff values for identifying sarcopenia in older Chinese adults

Sarcopenia, characterised by low muscle mass and muscle strength, is associated with poor health outcomes in older adults. Population-specific cutoffs are crucial for accurate diagnosis. This study aimed to identify the specific cutoff values for handgrip strength (HGS) and skeletal muscle mass index (SMI) to distinguish sarcopenic from non-sarcopenic individuals in the Chinese population. Data from the 2015 China Health and Retirement Longitudinal Study were used. HGS was measured with a digital hand dynamometer, and appendicular skeletal muscle mass (ASM) was determined using a validated anthropometric formula. SMI was calculated as ASM divided by height squared. A total of 4701 participants (71.8 ± 5.7 years) were included in the final analysis. Cutoff values were determined using receiver operating characteristic curve analysis, with usual gait speed ≤ 0.8 m/s as the outcome variable. The HGS cutoff values were 29.6 kg for men and 20.3 kg for women, while the SMI cutoffs were 7.3 kg/m² for men and 5.5 kg/m² for women. These values were higher than the Asian Working Group for Sarcopenia 2019 criteria. The findings provide clinically relevant, population-specific reference standards that may improve the accuracy of sarcopenia diagnosis in Chinese older adults.