FRIDAY, Nov. 22, 2002 (HealthDayNews) -- Frailty is a specific medical condition characterized by muscle weakness, lack of stamina, and weight loss.
And not everyone becomes frail as he or she ages. In fact, most people do not.
Now, researchers at Johns Hopkins University are beginning to discover why. It turns out that some people seem to be predisposed toward frailty, because they have certain biological "markers" such as inflammation, insulin resistance and increased blood-clotting activity.
By identifying these markers, doctors could potentially prevent or delay the onset of frailty.
"This is a very young field, but our hypothesis is that frailty is a biological syndrome, and that the weakness of frailty is a manifestation of something else," says Dr. Linda Fried, director of Johns Hopkins' Center on Aging and Health, and senior author of a study of frailty in nearly 5,000 people over the age of 65.
"We are pretty sure that this biology is complicated. Many systems are affected by aging, and it is the multitude of systems that are affected that create frailty," she says.
This is important, Fried says, because people afflicted with frailty are those most likely to suffer in old age.
"This is a most vulnerable, high-risk subset of older adults who are most likely to be hospitalized, become disabled and dependent," says Fried.
"There is a continuum of the severity of frailty, and a lot of the consequences may not be remediable, but there is evidence that some consequences are potentially preventable or treatable," she adds.
The results of Fried's study appear in the November issue of Archives of Internal Medicine. It uses data from the Cardiovascular Health Study and was supported by the National Institutes of Health.
Dr. Robert McCann, a geriatric specialist at the University of Rochester in New York, calls Fried's research a "fascinating study, the first that begins to explore the markers for frailty. Now we can start to come up with predictors for this condition, knowing that physical vulnerability doesn't necessarily have to lead to disability."
In the study, Fried and her colleagues found an association between frailty and increased inflammation, insulin resistance and increased blood-clotting activity.
Inflammatory cells are always present in the blood. But when they are stimulated over a long period of time, they have an adverse effect on many biological functions, Fried says.
"When stimulated, inflammatory cells can cause arthritis, contribute to the development of arteriosclerosis, and those with chronic inflammation are likely to lose muscle and bone mass," she says.
Those study subjects diagnosed with frailty were also more likely to suffer from insulin resistance, when the body is not able to use the insulin produced by the pancreas, the study reports.
Frailty was also associated with a mild increase in blood-clotting activity, Fried says, "which could be a consequence of chronic inflammation."
In the study, Fried and her colleagues used standardized criteria to identify frailty, including measuring grip strength, walking speed based on a distance 15 feet, unintentional weight loss of more than 10 pounds a year, daily feelings of exhaustion, and physical activity that used fewer than 400 calories a week.
Overall, 6.3 percent of the 4,735 study participants, age 65 or older, met the criteria of frailty. There were more frail women (7.3 percent) than men (4.9 percent). Forty-eight percent of the study participants were not frail, and 45.3 percent fell in an intermediate range, with some characteristics of frailty.
The prevalence of frailty increased with age, with 2.5 percent of those aged 65 to 70 meeting the criteria for frailty; 32 percent of those aged 90 and older met the criteria.
"We don't want people to run out and start taking anti-inflammatory medicine. Those decisions need to be based on more conclusions than we know now," Fried says. "But we could envision developing treatments to decrease frailty."
What To Do
The importance of exercise as you age is outlined at the National Institute on Aging. Because the Hopkins' study says women are at higher risk for frailty, they should check these American Medical Association tips for women and exercise.
