• Posted July 5, 2023

Slowed Walking Could Be Sign of Dementia in Dogs

Like people, dogs slow down as they age.

Researchers wondered whether slowed walking could also signal mental decline. To learn more, they did a series of experiments that included measuring the dogs' speed both on and off leash as well as cognitive testing.

"Walking speed in people is strongly associated with cognitive decline,"said study author Dr. Natasha Olby, chair in gerontology at the North Carolina State University College of Veterinary Medicine. "We hypothesized that the same might be true in dogs."

The study included 46 adult and 49 senior dogs. Researchers measured only gait speed in the adult dogs. For the senior dogs, they measured gait speed, did mental testing and asked owners to complete a cognitive assessment questionnaire.

The senior dogs were grouped together based on results of the questionnaire and their cognitive testing scores. Individual gait speed was measured first as a handler walked the dogs about 16 feet on a leash. Then they were offered a treat the same distance away and called to retrieve it off leash.

"The challenge with measuring gait speed is that dogs tend to match the speed of their handler when on leash, so we measured both on and off leash to see which was the most useful measure," Olby said in a university news release.

"Additionally, we are always concerned that body size and limb length will affect gait speed -- but if you see a Chihuahua and a Great Dane walking together off leash, the shorter one isn't always behind the other,"she added. "We found that on leash, size does correlate with gait speed, but off leash it doesn't make a difference. Capturing gait speed off leash lets us see the effects of both physical ability and food motivation."

Dogs in the last quarter of their expected life span moved more slowly than adult dogs, regardless of relative size, researchers found.

"Just as in humans, our walking speed is pretty stable through most of our lives, then it declines as we enter the last quarter or so of our life span,"Olby said.

And, researchers found, senior dogs who moved more slowly had more severe levels of mental decline based on the questionnaires. They also had poorer scores on the cognitive tests.

Joint pain did not seem to correlate with walking speed, though the study did not include dogs with severe osteoarthritis. Researchers hope to address that in the future.

When it comes to functional aging, mobility and cognition are key predictors, Olby said.

"Mobility relies heavily on sensory input, central processing and motor output -- in other words, the nervous system -- as a result, mobility and cognition are super-interconnected," she said. "When you have less mobility, the amount of input your nervous system gets is also reduced. It's not surprising that walking speed and dementia are correlated."

Olby said the exciting part of the study is not only that gait speed correlates with dementia in dogs as in people, but also that testing is easy since it is food-motivated and the distance is short.

"It could become a simple screening test for any veterinarian to perform on aging patients," Olby said.

The findings were recently published in the journal Frontiers in Veterinary Science.

More information

The American Veterinary Medical Association has more on caring for senior dogs and cats.

SOURCE: North Carolina State University, news release, June 27, 2023