A new study conducted by researchers from North Carolina State University explored one of the telltale signs of cognitive decline in dogs. According to their findings, older dogs who develop hearing loss may be on the road to dementia.
“In humans, we know that age-related hearing loss is estimated to affect one-third of people over age 65,” said researcher Natasha Olby. “We also know that the rate of cognitive decline is approximately 30-40% faster in people with age-related hearing loss and that hearing loss is a greater contributor to dementia risk than other factors such as hypertension or obesity. But we don’t understand where the same holds true for dogs.”
Understanding dogs’ cognitive function
The researchers performed cognitive and hearing assessments on nearly 40 older dogs and asked owners to answer questions about their pet’s quality of life and overall cognitive ability.
Ultimately, the team found a link between dogs who were struggling with their hearing and a decline in cognitive function. The researchers explained that 50 decibels (dBs) is a figure for average hearing ability among dogs. Nineteen of the dogs in the study were able to hear at 50 dBs, but 12 of the dogs could only hear at 70 dBs, and another eight dogs could only hear sounds at 90 dBs.
When comparing these results to the cognitive assessments, it was clear to the researchers that the dogs who struggled to hear were also struggling in other areas. Not only did their owners report lower scores related to companionship and vitality, but they noted that their pets were struggling with their usual commands and tasks.
The researchers hope these findings encourage consumers to pay closer attention to their aging dogs since there may be ways to combat hearing loss.
“Hearing loss is one of the biggest predictors of dementia in people,” said Olby. “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.
“This study indicates that the same connection is at work in aging dogs. 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 issue in humans.”