Older Adults Who are Weak, Have Low Muscle Mass and Poor Physical Functioning Run Increased Risk of Hospitalization
Monday, August 17, 2009
As adults get older, they tend to lose muscle and strength. In addition, their physical functioning may decline so that, among other things, they walk more slowly than they did when younger. As they get older, adults also run an increased risk of falls, bone fractures, hospitalizations, and disability.
New Research in the Journal of the American Geriatrics Society
To learn more about how different age-related changes in muscle, strength and physical functioning put older adults at risk of hospitalization, researchers recently studied more than 3,000 older adults over the course of about five years. All of the adults were between 70 and 80-years old when the study began. None of the adults were disabled or lived in nursing homes or other long-term care facilities.
At the start of the study, the researchers did a range of tests to measure each adult's strength and evaluate various characteristics of his or her muscles - including "muscle density" (the weight of a muscle relative to its size) and "low specific force of muscle" (the strength of a muscle relative to its size) . They also evaluated each adult's physical functioning by measuring, among other things, each adult's walking speed. About five years later, the researchers checked to see how many, and which, of the adults had been hospitalized since the study began.
Older adults who were weaker, had lower muscle density, lower specific force of muscle, or poorer physical functioning ran a higher risk of being hospitalized during the five-year period than other older adults, the researchers found. They also found that the more of these age-related changes in muscle and physical functioning that an adult had, the more likely it was that he or she would be hospitalized.
These findings suggest that a good way to determine whether an older adult runs an increased risk of hospitalization is to check for these four changes. Because slowed walking speed was the change most closely linked to increased risk of hospitalization and because walking speed can be measured cheaply and quickly at a healthcare providers' office, measuring walking speed appears to be a particularly good way to identify older adults at risk of hospitalization, the researchers suggest. Treatment and programs that focus on improving physical functioning, and building muscle density, strength, and muscle strength relative to muscle size, may be particularly effective in lowering risks of hospitalization, they write in The Journal of the American Geriatrics Society.
The summary above is from the full report titled, "Do Muscle Mass, Muscle Density, Strength and Physical Function Similarly Influence Risk of Hospitalization in Older Adults?" It is in the August 2009 issue of the Journal of the American Geriatrics Society (Volume 57, Issue 8). The report is authored by Peggy Mannen Cawthon, PhD, MPH, Kathleen M. Fox, MHS, PhD, Shravanthi. R. Gandra, PhD, MBA, Matthew J. Delmonico, PhD, MPH, Chiun-Fang Chiou, PhD, Mary S. Anthony, PhD, Ase Sewall, BS, Bret Goodpaster, PhD, Suzanne Satterfield, MD, DrPH, Steven R. Cummings, MD, Tamara B. Harris, MD, MS.