A recent study from North Carolina State University examined the connection between dementia and hearing loss in aging dogs. The results provide insight into how sensory loss impacts canine cognition and may help improve care for older dogs.
Corresponding author Dr. Natasha Olby, a professor at North Carolina State University School of Veterinary Medicine said, “In humans, we know that age-related hearing loss is estimated to affect one-third of people over age 65.”
Olby and colleagues examined 39 geriatric dogs for the study. Each dog underwent cognitive and auditory tests, and their owners completed two standard questionnaires, one on quality of life and the other on cognitive function. Age, questionnaire and cognitive testing results were compared between hearing groups. Each group’s dogs had an average age of 12, 13, and 14. T
“We also know that the rate of cognitive decline is approximately 30% to 40% faster in people with age-related hearing loss and that hearing loss is a greater contributor to dementia risk than other factors such as [high blood pressure] or obesity. But we don’t understand whether the same holds true for dogs,” Olby added in a university news release.
“Hearing loss is one of the biggest predictors of dementia in people,” Olby added. “Hearing loss also contributes to falls in elderly people, as sensory decline contributes to a loss in motor skills. So the connection between physical and neurological decline is clear for humans.”
The study’s findings revealed that “average” dogs have no trouble hearing tones at a volume of 50 decibels. At 50 dB, which is similar to a quiet refrigerator, 19 dogs could hear, followed by 12 at 70 dB, which is similar to a dishwasher, and eight at 90 dB, which is roughly equivalent to the noise produced by an airplane taking off.
“This study indicates that the same connection [seen in humans] is at work in aging dogs,” Olby explained. “But since we can potentially treat hearing loss in dogs, we may be able to alleviate some of these other issues. By quantifying neurological and physiological changes in elderly dogs, we’re not only improving our ability to identify and treat these issues in our pets, we’re also creating a model for improving our understanding of the same issues in humans.”
The findings were published online Saturday in the Journal of Veterinary Internal Medicine.