Not all signs of cognitive decline predict dementia – only 10% to 20% of people over the age of 65 have mild cognitive impairment or develop dementia the following year, according to the National Institute on Aging. “In many cases, the symptoms of mild cognitive impairment may persist over time or even improve,” says the institute.
A new study of nearly 17,000 adults over the age of 65 found that people who walk about 5% or more slowly each year, although showing signs of slower mental processing, are more likely to develop dementia. The study was published in the journal JAMA Network Open on Tuesday.
“These findings highlight the importance of walking to assess the risk of dementia,” wrote Taya Collyer, a researcher at Peninsula Clinical School at Monash University in Victoria, Australia.
The new study followed a group of 65-year-old Americans and 70-year-old Australians for seven years. Every two years, the people in the study were asked to take cognitive tests to measure their overall cognitive decline, memory, processing speed, and verbal fluency.
Every two years, participants were also asked to walk three meters. The two results were then calculated to determine the person’s normal gait.
At the end of the study, the researchers found that the highest risk of dementia was slowed down and also showed signs of cognitive decline in people.
The dual relationship between walking speed and memory decline is a predictor of future dementia, according to a 2020 meta-analysis of nearly 9,000 adults in the U.S..