Not all signs of cognitive decline predict dementia — only 10 to 20 percent of people age 65 and older have mild cognitive impairment or develop dementia within the next year, according to the National Institute on Aging. “In many cases, symptoms of mild cognitive impairment may persist over time or even improve,” the institute says.
A new study in nearly 17,000 adults over the age of 65 has found that people who walk about 5% slower or more each year, while showing signs of slowed mental processing, are more likely to develop dementia. . The study was published Tuesday in JAMA Network Open magazine.
“These findings underscore the importance of walking in assessing dementia risk,” wrote corresponding author Taya Collyer, a researcher at the Peninsula Clinical School at Monash University in Victoria, Australia.
The new study followed a group of Americans over 65 and Australians over 70 for seven years. Every two years, study participants had to take cognitive tests that measured overall cognitive decline, memory, processing speed and verbal fluency.
Twice every two years, participants were also asked to walk three meters. The two scores were then calculated to determine the person’s typical gait.
At the end of the study, the researchers found that the greatest risk of dementia was in people who walked more slowly and who, at the same time, also showed signs of cognitive decline.
A dual association between walking speed and memory decline is predictive of later dementia, according to a 2020 meta-analysis of nearly 9,000 American adults.