CHICAGO, Aug. 25 (Xinhua) -- People with weaker muscles, or low muscle strength, are 50 percent more likely to die earlier compared to their stronger peers after adjusting for sociodemographic factors, chronic health conditions and smoking history, a research of the University of Michigan (UM) found.
The researchers analyzed data of a nationally representative sample of 8,326 men and women aged 65 and older.
Grip strength can be measured using a device called a dynamometer, which a patient squeezes to measure their strength in kilograms. Researchers used "cut-points," or thresholds, to define levels of strength. Muscle weakness was identified as having a hand grip strength less than 39 kg for men and 22 kg for women.
Based on the data, 46 percent of the sample population was considered weak at baseline. By comparison, only about 10 to 13 percent were considered weak using other cut-points derived from less representative samples.
"Maintaining muscle strength throughout life, especially in later life, is extremely important for longevity and aging independently," said lead researcher Kate Duchowny, who recently completed her doctorate in epidemiology at the UM School of Public Health.
A growing body of research has indicated that muscle strength may be an even more important predictor of overall health and longevity than muscle mass, Duchowny said.
Additionally, hand grip strength specifically has been found to be inversely related to mobility limitations and disability. "This study further highlights the importance of integrating grip strength measurements into routine care, not just for older adults but even in midlife," said Duchowny. "Having hand grip strength be an integral part of routine care would allow for earlier interventions, which could lead to increased longevity and independence for individuals."
Many aging studies have been conducted on largely white populations. As the U.S. population becomes increasingly diverse, it is critical to use nationally representative data for these types of studies.
The study has been published in the Journal of Gerontology: Medical Sciences.
