Slow walking unveils shocking connection to dementia in aging dogs

According to a groundbreaking study conducted at North Carolina State University, dogs that experience a decline in physical mobility also exhibit a decline in mental sharpness. Researchers propose that measuring the gait speed of senior dogs could serve as a simple yet effective method to monitor their overall health and track the deterioration of their neurological function as they age.

Dr. Natasha Olby, the distinguished chair in Gerontology at NC State and the corresponding author of the study, explains, "We have long observed that walking speed in humans is closely associated with cognitive decline. We set out to investigate whether a similar relationship exists in dogs."

Olby and her team assessed the gait speed of 46 adult dogs and 49 senior dogs in an off-leash setting. While the adult dogs served as the control group and had their gait speed measured alone, the senior dogs underwent additional cognitive tests, and their owners completed the CADES questionnaire, a cognitive assessment tool. A higher CADES score indicates a more significant cognitive decline.

Based on the CADES scores and cognitive test results, the senior dogs were categorized into groups. Gait speed was then evaluated by initially walking the dogs on a leash over a five-meter distance with a handler, followed by placing a treat at the same distance away and calling the dogs to retrieve it without a leash.

Olby explains the challenges associated with measuring gait speed, stating, "One of the difficulties we encountered is that dogs tend to match the speed of their handler when on a leash. To determine the most useful measure, we conducted assessments both on and off leash."

She further elaborates, "We were also concerned about the potential impact of body size and limb length on gait speed. However, if you observe a chihuahua and a great dane walking together off leash, the smaller dog isn't always lagging behind the larger one. We discovered that while size does correlate with gait speed when dogs are on a leash, it doesn't make a difference when they are off leash. By capturing gait speed off leash, we can assess the combined effects of physical ability and food motivation."

The study revealed that, among senior dogs, size did not influence speed. In other words, dogs in the last 25% of their expected lifespan moved more slowly than adult dogs, regardless of their relative size.

Olby notes, "Similar to humans, our walking speed remains relatively stable throughout most of our lives, then declines as we enter the final quarter or so of our lifespan."

The study also found that senior dogs with slower gait speed exhibited more pronounced cognitive decline based on the owner-completed questionnaires and performed poorly on cognitive tests.

Although the researchers did not observe a correlation between joint pain and walking speed, they acknowledge that the program did not include dogs with severe osteoarthritis. Future research aims to address this aspect.

Olby emphasizes the crucial role of mobility and cognition in functional aging, stating, "When considering morbidity, mobility and cognition are the two most significant predictors. Mobility heavily relies on sensory input, central processing, and motor output—the nervous system. As a result, mobility and cognition are highly interconnected. When mobility declines, the nervous system receives reduced input. Hence, the correlation between walking speed and dementia is not surprising."

Excited about the study's implications, Olby adds, "What excites me most about this study is that it not only demonstrates the correlation between gait speed and dementia in dogs, similar to humans, but also highlights the ease of replicating our testing method. Since it relies on food motivation and covers a short distance, it could potentially become a simple screening test that veterinarians can perform on their aging patients."