Transitions in Sarcopenia Status and Cognitive Trajectories Among Middle-Aged and Older Adults in China: Longitudinal...

Baseline sarcopenia has been linked to cognitive decline in older adults; however, the impact of longitudinal changes in sarcopenia status on cognitive trajectories remains unclear.

This aims to examine the association between 2-year transitions in sarcopenia status and subsequent 5-year cognitive trajectories among middle-aged and older adults in China.

We analyzed data from 8189 participants (median age 58, IQR y; n=432952.9% female) in the China Health and Retirement Longitudinal Study. Sarcopenia status was determined in 2011 and 2013 according to the 2019 Asian Working Group for Sarcopenia criteria, and participants were classified into 7 transition groups based on status changes. Cognitive function was assessed from 2013 to 2018 using standardized z scores for executive function and episodic memory. Linear mixed-effects models were applied to evaluate associations between sarcopenia transitions and cognitive trajectories, adjusting for demographic, lifestyle, and health-related covariates.

Progression from a nonsarcopenic state was associated with greater cognitive decline compared to stable nonsarcopenia (β=-0.016, 95% CI -0.026 to -0.007; P<.001), with greater decline observed among those progressing from possible sarcopenia to sarcopenia (β=-0.027, 95% CI -0.054 to -0.001; P=.04). In contrast, regression from possible sarcopenia was associated with improved cognitive performance (β=0.028, 95% CI 0.015-0.041; P<.001). No significant improvement was observed among individuals regressing from established sarcopenia. Subgroup analyses showed consistent benefits of regression from possible sarcopenia across sex, age, residence, and education groups, except among urban residents (P=.05).

Progression in sarcopenia status was independently associated with accelerated cognitive decline, whereas regression from possible sarcopenia predicted cognitive benefit. These findings highlight possible sarcopenia as a clinically actionable and potentially reversible stage and underscore the importance of early identification and intervention to preserve cognitive health in aging populations.