Predicting Who’s at Risk for Mobility Disability

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Riding up an escalator is easy for Ethnea King, but don’t ask her to ride down.

“It gives me a weird feeling to look down,” says King, a Baltimore grandmother who turns 78 this month. “I had both knees replaced a few years back, and I’m afraid I won’t be able to move my legs forward.”

A widow who lives alone, King has become extremely cautious in her daily activities because she fears a fall could mean loss of the independence she treasures. She walks backward down the stairs to her laundry room, always holds onto handrails and uses a cane whenever she leaves the house.

King’s desire to stay independent prompted her to volunteer for a Johns Hopkins University study designed to predict whether older women will develop physical disabilities in the near future. The study results, published recently in the Archives of Internal Medicine, indicate that a series of simple tests can identify women at the highest risk of developing mobility disability within 18 months.


“People with this condition have difficulty in mobility-related tasks, such as walking three blocks, climbing steps and getting in and out of a car,” says the study’s lead author, Paulo Henrique M. Chaves, a Johns Hopkins geriatrician who is also an assistant professor at Brazil’s University of Rio de Janeiro. “It affects about 35% to 50% of women 70 and older and is the entry door to a series of changes that lead to further functional deterioration, which will ultimately lead to moving to assisted-living settings or nursing homes.”

The first test involves asking a woman if health problems or physical conditions have prompted her to adapt the ways she performs daily tasks. The other two tests measure the time it takes her to walk one meter and determine how long she can balance on one leg. By plugging the answers into a series of graphs, care providers can quickly determine the likelihood that a woman will develop some degree of disability in the near future.

For example, a woman who takes two seconds to walk one meter, can balance on one leg for less than 10 seconds and has substantially altered the way she does tasks has a 56% probability of developing mobility disability within 18 months, Chaves says. In contrast, a woman who takes one second to walk one meter, can balance on one leg for 30 seconds and has not altered her activities of daily life has a 3% probability of developing mobility disability within the same time period.

“The idea is that it’s much easier to try and prevent disability instead of waiting for difficulty to happen, then doing rehabilitation,” says Chaves, who adds that these tests can identify declines in function before they are apparent.

Although several tests exist to assess mobility and predict subsequent loss, none was quick and easy enough to do during a routine medical exam, says the study’s coauthor, Linda P. Fried, director of the Johns Hopkins Center on Aging and Health. “We wanted to develop a simple, inexpensive tool doctors could use in clinical decision-making,” she says.

“Mobility disability is a highly prevalent public health concern that is a major risk factor for difficulty and dependency in other areas and for decreased quality of life in older adults,” Fried says. “In the last 10 to 15 years, there’s been increasing recognition that disability can, to a certain extent, be prevented or postponed. This screening tool can help target women who can benefit most from preventive interventions.”


Among the interventions that may be prescribed for women at high risk are balance training and exercises to increase strength, endurance and flexibility. Hopkins researchers are working to determine which programs are most effective.

“The best prevention and treatment we know of is physical activity,” says Jack Guralnik, chief of the epidemiology and demographics office at the National Institute on Aging, adding that “simply having people increase the amount they walk can be extremely helpful.”

One of the best ways to help older adults maintain function and avoid disability is to encourage them to continue to do as much as possible in the community and at home, says C. Jessie Jones, co-director of the Center for Successful Aging at Cal State Fullerton.

“Things like taking the stairs, playing with grandchildren and washing the car are all helpful because they work many of the body’s systems together,” she says. “Unfortunately, technology has taken away our need to do many physical activities, so it’s important to add as much movement as possible back into our lifestyle. And it’s never too late to start.”

Just as lifestyle activities can help maintain fitness and function, inactivity can lead to their loss. This can become a vicious spiral, where sedentary habits lead to mobility difficulty, which leads to further inactivity. The end stage of this process can be muscles that are so weak that seniors are institutionalized because they need help with tasks as simple as getting out of a chair.

Although staying active is beneficial for everyone, Jones says, “the idea of moving more and sitting less is particularly important for older adults, since the use-it-or-lose-it phenomenon becomes increasingly more [significant] with age.”


In addition to incorporating activity into daily routines, she says, most older adults also can benefit from setting aside time each day for specific strength, aerobic and flexibility exercises. Those who want to exercise at home might consider seeking help from a physical therapist or qualified senior-fitness specialist in setting up a program. Others might prefer participating in a structured program at a senior center, YMCA or other facility.

“Older adults need to recognize that avoiding functional problems will not make them go away,” adds the Fullerton center’s co-director Debra Rose. “In fact, becoming less active will only make the problems worse.”


* “Exercise: A Guide from the National Institute on Aging” is free by calling (800) 222-2225. A companion video is available for $7, payable to the National Institute on Aging, by writing NIA Information Center, Department F, P.O. Box 8057, Gaithersburg, MD 20898.

* The American Senior Fitness Assn. will refer people to qualified instructors in their areas. Call (800) 243-1478 or visit the Web site at

* Fifty-Plus Fitness Assn. offers resources and activities for older adults who want to get fit--and stay fit. Call (650) 323-6160 or visit the Web site