Overview: Muscle weakness characterized by grip strength was associated with accelerated biological aging, a new study reports.
Source: University of Michigan
Everyone ages at a different rate. That’s why, despite living the same number of years, two 50-year-olds can have different biological ages – meaning that a multitude of intrinsic and extrinsic factors have caused them to age at different rates with different levels of disease risk. and early death.
Lifestyle choices, such as diet, smoking, and illness all contribute to accelerating biological age beyond a person’s chronological age. In other words, your body is aging faster than expected.
And for the first time, researchers have found that muscle weakness characterized by grip strength, a measure of overall strength capacity, is associated with accelerated biological age.
Specifically, the weaker your grip strength, the older your biological age, according to results published in the Journal of Cachexia, Sarcopenia and Muscle.
Michigan Medicine researchers modeled the relationship between biological age and grip strength of 1,274 middle-aged and older adults using three “age accelerator clocks” based on DNA methylation, a process that provides a molecular biomarker and estimator of the rate of aging. The clocks were originally modeled from various studies on diabetes, cardiovascular disease, cancer, physical disabilities, Alzheimer’s disease, inflammation and early death.
The results show that both older men and women showed an association between lower grip strength and biological age acceleration across the DNA methylation clocks.
“We know that muscle strength is a predictor of longevity, and that weakness is a powerful indicator of disease and death, but for the first time, we have found strong evidence of a biological link between muscle weakness and actual acceleration in biological age,” says Mark Peterson, Ph.D., MS, lead author of the study and associate professor of physical medicine and rehabilitation at the University of Michigan.
“This suggests that if you maintain your muscle strength throughout your lifespan, you may be able to protect yourself against common diseases of old age. We know that smoking, for example, can be a powerful predictor of illness and death, but now we know that muscle weakness could be the new smoking.” to be.”
The real strength of this study was in its 8 to 10-year observation, in which lower grip strength predicted faster biological aging measured up to a decade later, said Jessica Faul, Ph.D., MPH, a co-author of the study and research associate professor at the UM Institute for Social Research.
Previous studies have shown that low grip strength is an extremely strong predictor of adverse health effects. One study even found it to be a better predictor of cardiovascular events, such as myocardial infarction, than systolic blood pressure — the clinical hallmark for detecting heart disease. Peterson and his team have previously shown a robust association between frailty and chronic disease and mortality in populations.
This evidence combined with the recent findings of their study, Peterson says, shows that clinicians can leverage the use of grip strength as a way to screen individuals for future risk of functional decline, chronic disease and even early death.
“Screening for grip strength would provide an opportunity to design interventions to delay or prevent the onset or progression of these adverse ‘age-related’ health events,” he said.
“We have been pushing for clinicians to start using grip strength in their clinics and only geriatrics have included this kind. However, not many people use this, although we have seen hundreds of publications showing that grip strength is a really good measure of health.”
Researchers say future research is needed to understand the link between grip strength and age acceleration, including how inflammatory conditions contribute to age-related weakness and mortality.
Previous studies have shown that chronic inflammation with aging – known as “inflammatory” – is a major risk factor for death in older adults. This inflammation is also associated with lower grip strength and may be a significant predictor on the path between lower grip strength and both disability and multimorbidity from chronic disease.
In addition, Peterson says, studies should focus on how lifestyle and behavioral factors, such as physical activity and diet, can influence grip strength and age acceleration.
“Healthy eating habits are very important, but I think regular exercise is the most important thing a person can do to maintain health throughout life,” he said. “We can show it with a biomarker like DNA methylation age, and we can also test it with a clinical feature like grip strength.”
Other authors include Stacey Collins, MA, Helen CS Meier, Ph.D., MPH, Alexander Brahmsteadt, MD, all of the University of Michigan.
About this research news about aging and muscle strength
Author: Noah Fromson
Source: University of Michigan
Contact: Noah Fromson – University of Michigan
Image: The image is attributed to Justine Ross, Michigan Medicine
Original research: Open access.
“Handle strength is inversely associated with acceleration of DNA methylation age” by Mark D. Peterson et al. Journal of Cachexia, Sarcopenia and Muscle
Grip strength is inversely associated with age acceleration of DNA methylation
There is a large body of evidence that muscle weakness, as determined by low grip strength, is associated with a wide range of negative health-related health outcomes. Given these associations, grip strength has been labeled a ‘biomarker of aging’; and yet the pathways linking grip strength to negative health consequences are unclear. The aim of this study was to determine whether grip strength was associated with measurements of DNA methylation (DNAm) age acceleration.
Middle-aged and older adults from the 2006 to 2008 waves of the Health and Retirement Study with a follow-up of 8-10 years were included. Cross-sectional and longitudinal regression modeling was performed to examine the association between normalized grip strength (NGS) and three measures of DNAm age acceleration, adjusted for cell composition, sociodemographic variables and smoking. Longitudinal modeling was also completed to investigate the association between change in absolute grip strength and DNAm age acceleration. The three DNAm clocks used for age acceleration estimation are the established DunedinPoAm, PhenoAge and GrimAge clocks.
There was a robust and independent cross-sectional association between NGS and DNAm age acceleration for men using the DunedinPoAm (β: -0.36; p <0.001), PhenoAge (β: −8.27; p = 0.01) and GrimAge (β: -4.56; p = 0.01) clocks and for women using the DunedinPoAm (β: −0.36; p < 0.001) and GrimAge (β: −4.46; p = 0.01) clocks. There was also an independent longitudinal association between baseline NGS and DNAm age acceleration for men (β: −0.26; p <0.001) and women (β: −0.36; p <0.001) using the DunedinPoAm clock and for women using only the PhenoAge (β: −8.20; p <0.001) and GrimAge (β: −5.91; p < 0.001) clocks. Longitudinal modeling revealed a robust association between change in grip strength from wave 1 to wave 3 was independently associated with PhenoAgeAA (β: −0.13; 95% CI: −0.23, −0.03) and GrimAgeAA (β: −0.07; 95% CI: − 0.14, −0.01) only in males (both p < 0.05).
Our findings provide some first evidence of age acceleration in men and women with lower NGS and loss of strength over time. Future research is needed to gain insight into the extent to which DNA age mediates the association between grip strength and chronic disease, disability and mortality.