E-News Exclusive

Gait Speed as a Longevity Indicator
By Barbara Worthington

Is it a casual stroll, a brisk walk, or a painfully snail-like saunter? A recent study indicates the walking speed of older adults in their 60s and 70s represents a strong predictor of how long they’re likely to live. The study shows that those who walk faster are more than twice as likely to be living 10 years later. And the survival gap between fast and slow walkers is even greater at 15 years.

Stephanie Studenski, MD, a physician who specializes in geriatrics and serves as a professor of medicine at the University of Pittsburgh, presented the data at the 19th International Association of Gerontology and Geriatrics World Congress of Gerontology and Geriatrics. The study included a pooled analysis of nine studies that observed more than 34,000 older adults. Findings indicate that elders who displayed the ability to walk faster are more than twice as likely (92% vs. 45%) to be alive after 10 years.

Fifteen years after the gait observations, the survival gap between the fast and slow walkers became even greater (83% vs. 34%). Indications from previously conducted research revealed that a slow walking speed in older adults is also associated with sarcopenia, an age-related condition that involves a progressive decline in muscle mass, strength, and function.

Studenski indicates that the findings linking older adult gait with longevity present a useful clinical correlation. “The ability to walk depends on many, many of the body’s functions,” she says. In addition to body support, timing, and power, walking requires adequate effort from both the heart and the lungs. It incorporates the nerve coordination of the brain, spinal cord, and peripheral nerves. And it requires the support of the muscles, bones, and joints.

“Walking reflects the function of many organ systems,” she says. “It’s a core indicator of the proper working of many body systems in older people.” The report involves older adults aged 60 to more than 90 years old. Studenski confirms that the relationship between gait speed and longevity “is true for all of them.”

Because of gait speed’s ability to reflect the working of many organ systems, it may contribute to estimating the overall burden on older adults’ disease, serving as a predictor of multiple outcomes. Studenski says elders’ walking speed may eventually be used clinically as a type of vital sign similar to other basic indicators of their health status such as temperature, blood pressure, or respiratory rate.

Gait Indications
Although the study excluded older adults under the age of 60, Studenski says that for individuals in their 40s and 50s, the measure of grip strength among those demographics can also predict how health will progress later in life. However, after the age of 60, she says, the ability to move around is a reliable indicator of overall health. “After age 60, people’s moving ability impacts their walking ability,” she says.

Study results indicate the overall 10-year survival was 45% for older adults with gait speeds less than or equal to 0.4 m/second compared with 92% for elders with gait speeds greater than or equal to 1.4 m/second. The overall 15-year survival rate was 34% for elders with gait speeds less than or equal to 0.4 m/second compared with 83% for those with gait speeds greater than or equal to 1.4 m/second.

The finding of the gait speed/longevity correlation proved to be consistent among many subgroups, including gender, ethnicity, and health status. The research highlighted the association between a slow gait and sarcopenia. Sarcopenia can increase the risk of falls and disability, contribute to the development of other diseases, and compromise quality of life.

Promising Possibilities
The study findings yield information beneficial to professionals who work with aging patients and clients. “The data suggest your walking speed helps discern who’s going to be alive 20 years later,” says Studenski, indicating that such information can be valuable in several ways.

Reliable gait speed analysis can help practitioners with determining a prognosis for older adults’ life expectancy, according to Studenski. If gait speed is decreasing, practitioners can take steps to evaluate what has changed and assess the possibility of deterioration in a particular organ system or systems.

Based on elders’ gait speed, practitioners can seek a treatment goal to improve walking. For example, Studenski says, if an elder suffers from congestive heart failure leading to shortness of breath and excessive fatigue, practitioners may seek to improve the ability to walk and subsequently “measure the effect of the treatment they make.”

One factor that contributes to walking very slowly, according to Studenski, is insufficient muscle mass. The finding of such an insufficiency can lead practitioners to the development of new treatments, she says. Older adults’ gait speed analysis “can help identify people who are very likely to be alive in 10 years and could be appropriate for different types of preventive measures.”

— Barbara Worthington is editor of Aging Well.