Walking Speed May Predict Longevity

Gait speed, or walking speed, has previously been suggested as a potentially useful clinical indicator of well-being among older adults.  Stephanie Studenski, from the University of Pittsburgh (Pennsylvania, USA), and colleagues assessed the association of gait speed with survival in older adults, aiming to determine the degree to which gait speed explains variability in survival. The researchers pooled analysis of 9 participating studies, involving data from 34,485 community-dwelling adults age 65 years or older at the study’s start, who were followed for a period from 6 to 21 years.  Gait speed was calculated for each participant using distance in meters and time in seconds, with subjects instructed  to walk at usual pace and from a standing start for a distance of up to 6 meters. The average gait speed of the participants was 0.92 meters (3 feet) per second.   Correlating the incidences of death during the follow-up period, the team found that gait speed was associated with differences in the probability of survival at all ages in both sexes, but was especially informative after age 75 years. At this age, predicted 10-year survival across the range of gait speeds ranged from 19% to 87% in men, and from 35%  to 91% in women.   The authors suggest there are several reasons why gait speed may predict survival, positing that: "Walking requires energy, movement control, and support and places demands on multiple organ systems, including the heart, lungs, circulatory, nervous, and musculoskeletal systems. Slowing gait may reflect both damaged systems and a high energy cost of walking."