Association Between Sarcopenia and Cognitive Impairment: A Systematic Review and Meta-Analysis

Sarcopenia, a gradual loss of muscle mass and function, has been associated with poor health outcomes. Its correlation with another age-related degenerative process, impaired cognition, remains uncertain. This meta-analysis aimed to determine whether there is an association between sarcopenia and cognitive impairment.

PubMed and Scopus were searched for observational studies that investigated the association between sarcopenia and cognitive dysfunction. Participants' demographics and measurements, definition of sarcopenia, and tools for evaluating cognitive function were retrieved. The correlations between sarcopenia and cognitive impairment were expressed as crude and adjusted odds ratios with 95% confidence intervals (CIs).

Seven cross-sectional studies comprising 5994 participants were included. The crude and adjusted odds ratios were 2.926 (95% CI, 2.297-3.728) and 2.246 (95% CI, 1.210-4.168), respectively. The subgroup analysis showed that different target populations and sex specificity did not significantly modify the association, whereas the tools for evaluating cognitive function and modalities for measuring body composition did.

Sarcopenia was independently associated with cognitive impairment. Future cohort studies are warranted to clarify the causal correlation. The inclusion of relevant biomarkers and functional measurements is also recommended to elucidate the underlying biological mechanism.