Age-associated decline of muscle mass, grip strength and gait speed: a 4-year longitudinal study of 3018 community-dwelling older Chinese.

Aims: Studies about sarcopenia in Asia are fewer, and started later than in Europe and America. We attempted to examine the decline in muscle mass, grip strength and gait speed in a cohort of older Chinese prospectively over 4 years.

Methods: We recruited 4000 community-living Chinese older than 64 years, and measured their appendicular skeletal mass (ASM) by dual-energy X-ray absorptiometry, grip strength, and gait speed at baseline and after 2 years. Muscle mass and gait speed were additionally measured after 4 years.

Results: After 4 years, 3018 participants completed all the measurements. The annualized decline in grip strength (-0.798 kg/year vs -1.239 kg/year) and gait speed (-0.019 m/s/year vs - 0.025 m/s/year) was faster in women than in men. Muscle mass was relatively preserved in comparison with grip strength and gait speed. The percentage loss of ASM in 4 years was -1.59% and -2.02% in men and women, respectively. The percentage decline in gait speed after 4 years was -8.2% in men and -9.0% in women. However, the decline in grip strength was more rapid, particularly in women, which was -10.0% in 2 years and less so in men, -3.85% in 2 years.

Conclusion: Compared with black people and white people, the older Chinese have less muscle mass, weaker grip strength and slower gait speed. Although the rate of loss of ASM was modest, the decline in gait speed was rapid and the decline in grip strength was particularly fast in older Chinese women.