Causal relationship between hand grip strength and cognition/dementia risk: a Mendelian randomization study

Area of Science:

• Neuroscience
• Genetics
• Public Health

Background:

• Muscle strength, particularly hand grip strength, is known to correlate with cognitive function.
• The bidirectional causal relationship between hand grip strength and cognition remains incompletely understood and presents a public health challenge.
• This study investigates the causal link between hand grip strength and cognitive function, and its potential impact on dementia risk.

Purpose of the Study:

• To explore the causal relationship between hand grip strength and cognitive function.
• To determine if hand grip strength causally influences dementia risk.
• To provide insights for public health interventions aimed at cognitive health.

Main Methods:

• Utilized a two-sample Mendelian randomization (MR) analysis.
• Employed genome-wide significant single nucleotide polymorphisms (SNPs) associated with hand grip strength and cognition/dementia risk.
• Applied inverse variance weighted (IVW) method for primary analysis, with weighted mode and MR-Egger for sensitivity analyses.

Main Results:

• A positive causal effect of hand grip strength (both left and right) on cognitive function and performance was observed.
• No significant reverse causality was found between cognitive function/performance and hand grip strength.
• No evidence supported a causal effect of hand grip strength on dementia risk.

Conclusions:

• Hand grip strength has a positive directional causal influence on cognitive function.
• No causal link was identified between hand grip strength and dementia.
• Findings have implications for public health strategies targeting cognitive decline prevention.