A causal relationship between sarcopenia and cognitive impairment: A Mendelian randomization study.

Area of Science:

• Gerontology
• Neuroscience
• Genetics

Background:

• Sarcopenia and cognitive impairment are prevalent conditions in the elderly.
• These conditions frequently coexist, suggesting a potential shared etiology or interaction.

Purpose of the Study:

• To investigate the causal relationship between sarcopenia-related muscle characteristics and cognitive performance in older adults.
• To explore the bidirectional nature of this relationship using genetic association methods.

Main Methods:

• Utilized linkage disequilibrium score regression (LDSC) and Mendelian Randomization (MR) analyses.
• Employed genome-wide association study (GWAS) meta-analyses on discovery and replication samples.
• Performed univariate and multivariable MR analyses to assess causal effects.

Main Results:

• Appendicular lean mass (ALM) and walking pace showed a significant causal relationship with cognitive function.
• Low grip strength was not found to be causally associated with cognitive function.
• Reverse causality analyses confirmed a causal link from cognitive function to ALM and walking pace.

Conclusions:

• Sarcopenia-related muscle characteristics and cognitive performance are causally linked in a bidirectional manner.
• Low ALM and slow walking pace are identified as causal factors contributing to reduced cognitive performance.
• Findings suggest a significant causal relationship between sarcopenia and cognitive impairment in older adults, offering insights for prevention and treatment.