Bidirectional Relationship among Cognitive Function, Muscle Mass, and Grip Strength in Older Adults: the BUSAN Study

With the increasing number of older individuals, understanding the interplay among muscle strength, muscle mass, and cognitive functions in aging populations is important. This study aimed to investigate the relationships among muscle mass, muscle strength, and cognitive function among older adults, with a focus on understanding the bidirectional correlations among these factors.

A total of 335 participants aged ≥65 years were analyzed. Comprehensive assessments, including body composition measurements, cognitive function evaluations using the Korean version of Mini-Mental State Examination (K-MMSE), tablet-based cognitive tests, and grip strength measurements were conducted. Statistical analyses included Spearman correlation and binary logistic regression explore the relationships among muscle mass, grip strength, and cognitive function while adjusting for potential confounders.

Significant correlations were observed among grip strength, lean and skeletal muscle mass index, and cognitive function. Lower grip strength was associated with lower K-MMSE scores, indicating a higher risk of cognitive decline. But lean and skeletal muscle masses index were not associated with cognitive decline. Further analysis revealed a bidirectional relationship, with cognitive decline being associated with reduced grip strength.

Maintaining muscle strength and mass are important potential strategies to support cognitive health in older individuals. These findings suggest a potential reciprocal relationship where better cognitive function may also contribute to the maintenance or improvement of grip strength. This interconnectedness highlights the importance of considering both physical and cognitive health in aging populations.