Grip strength is inversely associated with DNA methylation age acceleration

Area of Science:

• Gerontology
• Epigenetics
• Biomarkers of Aging

Background:

• Muscular weakness, indicated by low grip strength, is associated with adverse aging outcomes.
• Grip strength is considered a biomarker of aging, but the underlying mechanisms are not fully understood.
• This study investigates the relationship between grip strength and DNA methylation (DNAm) age acceleration.

Purpose of the Study:

• To determine if grip strength is associated with DNAm age acceleration.
• To explore the link between grip strength as a biomarker of aging and epigenetic aging markers.

Main Methods:

• Utilized data from middle-aged and older adults in the Health and Retirement Study (2006-2008 waves).
• Employed cross-sectional and longitudinal regression modeling to analyze the association between normalized grip strength (NGS) and three DNAm age acceleration clocks (DunedinPoAm, PhenoAge, GrimAge).
• Adjusted for covariates including cell composition, sociodemographics, and smoking status.

Main Results:

• A significant, independent cross-sectional association was found between NGS and DNAm age acceleration in both men and women across multiple clocks.
• Longitudinal analysis revealed independent associations between baseline NGS and DNAm age acceleration.
• Changes in grip strength over time were also robustly associated with DNAm age acceleration, particularly in men.

Conclusions:

• Findings suggest initial evidence of age acceleration in individuals with lower grip strength and strength decline.
• Lower grip strength and loss of strength may be linked to epigenetic aging processes.
• Further research is required to elucidate the role of DNAm age in mediating the relationship between grip strength and health outcomes like chronic disease, disability, and mortality.