Fewer trips outside neighborhood tied to frailty

By Joene Hendry

NEW YORK (Reuters Health) - A decline in mobility by older people outside of their neighborhoods may be an early predictor of frailty, researchers report.

Dr. Qian-Li Xue, and colleagues at Johns Hopkins University in Baltimore, Maryland studied how restricted life-space -- the area one purposely moves through to perform regular daily activities -- is associated with the development of frailty.

For 3 years they followed 599 women, who at age 65 years or older were moderately or severely disabled with cardiovascular, muscle or skeletal, neurologic, or lung disease -- or had diabetes or cancer. However, they had no specific signs of frailty, such as muscle weakness, slow walking speed, low levels of physical activity, a general sense of fatigue, and weight loss.

The researchers used yearly questionnaires to access the women's mobility. At the start of the study 51 women reported never leaving their home (severely constricted), and 107 said they left their home but remained in their neighborhood (moderately constricted).

Another 247 women were slightly constricted (left the neighborhood fewer than four times weekly) and 194 women who ventured outside their neighborhood four or more times weekly were listed as non-constricted.

Over 3 years, 186 women (31 percent) became frail, the researchers report in the American Journal of Epidemiology.

Compared with women in the non-constricted group, "the risk of becoming frail was 1.7 times higher for women with slightly constricted life-space," Xue told Reuters Health. This suggests "a slightly constricted life-space may serve as an early warning sign for development of frailty," he added.

Seventy-one women (12 percent) died over the study period without showing signs of frailty in the yearly assessments. Moreover, dying before showing evidence of frailty was significantly more prevalent among women with moderate or severe life-space constriction.

These findings further suggest that frailty may develop over a few months and that yearly assessments may not identify the condition in time to offer interventions, Xue added.

This study provides the first evidence that a slightly constricted life space may be an early marker for the development of frailty, whereas severe life space constriction may suggest a high risk of mortality, among community-dwelling elders, Xue and colleagues conclude.

SOURCE: American Journal of Epidemiology, January 15, 2008