Unexplained weight loss, exhaustion, a weak grip, slow walking speed and low energy--the hallmarks of frailty--are most likely to strike women, African-Americans, the less educated and the poor, according to a nationwide study of more than 5,000 older adults.
Results of the multicenter study, the first to study frailty in depth, are published in the March issue of the Journal of Gerontology: Medical Sciences.
"As physicians, we've always thought that we knew how to identify a frail person, yet there's been no agreement on how to do that and no standard definition for the condition," says Linda P. Fried, director of Hopkins' Center on Aging and Health and lead author of the report. "Now that we have our hallmarks, we can determine the causes and consequences of frailty and ways to prevent or treat it."
Those frail at the start of the study were six times more likely to die than those who weren't over a three-year period, and more than three times more likely to die over a seven-year period. After seven years, 43 percent of those who were frail had died, compared to 23 percent of those who were intermediate and 12 percent of those who were robust.
Because 20 percent of the population is now over the age of 65, compared with only 4 percent a century ago, and because frailty affects 5 to 20 percent of this age group, the condition "is a concern not just for geriatricians but for all physicians who see older adults," Fried says. "These patients are the most vulnerable, most at risk for disability or death, the highest users of medical care and at the highest risk of being admitted to nursing homes."
Researchers studied 5,317 people ages 65 to 101 who lived on their own. Fifty-eight percent were female and 15 percent African-American, with a broad range of socioeconomic, functional and health status. The study subjects were participating in the Cardiovascular Health Study, a prospective, observational study of men and women at least 65 years old in four areas of the country: Sacramento County, Calif.; Washington County, Md.; Forsyth County, N.C.; and Allegheny County, Pa.
The clinicians did physical exams and lifestyle evaluations, including assessing difficulty in performing daily tasks. They concluded that a diagnosis of frailty requires at least three of the following symptoms: shrinking (unintentional weight loss of at least 10 pounds or 5 percent of body weight compared to a year earlier), weakness (grip strength in the lowest 20th percentile), poor endurance and energy (self-reported exhaustion), slowness (the most time it takes to walk 15 feet) and low physical activity level (the lowest 20th percentile of physical activity, compared to the rest of the subjects).
Overall, 7 percent of the group had at least three criteria for frailty, while 46 percent had none. Six percent of the initial group and 12 percent of the African-American group were frail. Prevalence of frailty increased with each five-year age group.
Those who were frail were older (ages 75 to 84), more likely to be female (69 percent) and African-American (28 percent), and also had higher rates of disability and co-existing chronic diseases, including arthritis, high blood pressure and diabetes.
In addition, those who were intermediate at the start of the study were twice as likely to become frail over three years relative to those with no frailty characteristics.
The study was supported by the National Heart, Lung and Blood Institute. Other institutions involved in the study were the University of Washington; University of Pittsburgh; University of California, Davis; St. Francis Hospital in Roslyn, N.Y.; University of California, Los Angeles; University of Vermont; Uniformed Services University of the Health Sciences; and Wake Forest University School of Medicine.
Related Web sites:
National Heart, Lung and Blood Institute: www.nhlbi.nih.gov
National Institute on Aging: www.nih.gov/nia