Leading veterinary neurologist Natasha Olby took her research into Canine Cognitive Dysfunction Syndrome to the next level by convening a group of 12 experts from across the world to craft diagnostic criteria for the syndrome, which is analogous to early Alzheimer’s disease in humans.

This month, the Journal of the American Veterinary Medical Association approved publication of the guidelines, which the group started working on in January and finalized over a two-day meeting in August in Raleigh. 

“The guidelines are only the start of the process of defining and identifying cognitive decline and dysfunction in dogs,” says Olby, the Dr. Kady M. Gjessing and Rahna M. Davidson Distinguished Chair in Gerontology at NC State. “They have been developed to be accessible to primary veterinarians and their pet owners and will help to unify efforts to detect cognitive decline in its early stages.”

Canine Cognitive Dysfunction Syndrome, like Alzheimer’s disease, is linked to the development of amyloid plaques and cortical atrophy, a progressive degeneration of brain tissue. CCDS had been diagnosed based on ruling out any obvious physical conditions and on a dog owner’s answers to a questionnaire.

Research into aging dogs is particularly valuable for Alzheimer’s researchers because six months of a dog’s life is the equivalent of three or four years in humans, which means veterinarians can do clinical trials on aging much more efficiently. 

Olby has been a leader in the study of aging since receiving NC State University’s largest endowed professorship in 2017. In a groundbreaking study that started in 2018, she and Dr. Margaret Gruen, professor of behavioral medicine at the NC State College of Veterinary Medicine, collaborated to develop ways to quantify changes in cognition, mobility and sensory loss in older dogs and to use the measurements to describe how the nervous system ages in dogs. Their research spanned cognitive testing, sleep quality, postural stability, gait speed, muscle strength and hearing, vision and smell skills.

With ways to measure decline confirmed, the next step was to define what criteria merit a diagnosis of Canine Cognitive Dysfunction Syndrome in aging animals. Developing the process for diagnosing Alzheimer’s in humans took decades and continues to evolve due to the complex interplay of many neurodegenerative processes.

“We have just started the process for CCDS, but our definitions should help to unify the clinical and research world in their efforts to understand more about this common age-associated syndrome,” Olby says. “The cognitive changes that happen with canine cognitive dysfunction can also be caused by many different conditions, both systemic and within the brain, and so these need to be ruled out before a diagnosis of CCDS can be made.” 

The guidelines to diagnose Alzheimer’s disease in people focus on identifying an appropriate history of changes, documenting memory and cognitive changes with questionnaires and tests and ruling out other conditions with a full work up and brain MRI, Olby says. More recently, clinicians have been able to use blood and cerebral spinal fluid markers as well as conduct specific tests for amyloid accumulation on an MRI. 

“Work in dogs is progressing along the same lines but lacks detailed information describing healthy versus abnormal test results in large populations of dogs,” she says. “Also, MRIs involve significant expense as well as anesthetic risk.”

Since January, Olby and the rest of the Canine Cognitive Dysfunction Working Group have reviewed all canine literature and concluded that not enough evidence exists to make recommendations on blood biomarkers. 

“But we do have enough consensus to start the process with some practical guidelines that everyone can use,” she says. 

The guidelines: 

• Highlight the appropriate clinical history.
• Explain how to use caregiver questionnaires for screening and for monitoring.
• Provide a list of diagnostic tests that should be completed at minimum.

“They also stress the importance of re-evaluating patients after comorbidities that could cause similar signs have been treated,” Olby says. “They then provide a higher tier of diagnosis that incorporates MRI and CSF analysis.” 

Olby applied for and won a grant from the AKC to convene the group of experts a day before the 2025 AKC Canine Health Foundation National Parent Club Canine Health Conference in Durham. She then presented what the Canine Cognitive Dysfunction Syndrome Working Group crafted as guidance in diagnosing canine dementia.

The working group included three veterinary neurologists, two veterinary behaviorists, two primary practitioners with a focus on senior dogs, a canine ethologist, a human neuropathologist, a veterinary radiologist and two basic science researchers. All participants had either worked extensively on CCDS or were actively involved with ongoing Canine Cognitive Dysfunction Syndrome studies. 

“The in-person meeting was a unique opportunity for us to spend two days focused on synthesizing the work we had already done to produce guidelines that made sense to us all,” Olby says.

A white paper describing the guidelines is scheduled to be published on JAVMA’s website this month.