Q & A: Cognitive Dysfunction in Pets
By Dr. Kim Everson, DVM
Question: My dog is almost 14-years-old and he has been acting very strangely in the last few months. Do dogs get Alzheimer’s disease?
Answer: Senior dogs can indeed develop a form of dementia referred to generally as canine cognitive dysfunction syndrome. Some common clinical signs of canine cognitive dysfunction include:
- disorientation
- decreased socialization
- loss of housebreaking (i.e., soiling in the house)
- altered sleep patterns (i.e., reversing days and nights)
- alterations in learned behaviors (e.g., forgetting or ignoring old household rules)
- excessive barking
- aggressiveness
Numerous disease processes within the brain contribute to these age-related behavior changes including shrinking brain mass, mineral or “plaque” deposits, oxidative damage, or decreased blood flow (e.g., “stroke”). Very specialized tests are required to evaluate a dog’s brain which makes cognitive dysfunction challenging to diagnose. Instead, cognitive dysfunction is usually identified by ruling out other common age-related diseases.
When there is concern about a senior dog’s mental ability, he should first be given a thorough physical examination by his veterinarian. Some dogs lose their hearing or have decreased vision as they age making them seem confused or less social. Blindness or deafness can be adapted to as long as the owner understands the dog’s needs. Painfulness from severe dental disease or arthritis, for example, can increase a pet’s irritability or cause him to have accidents in the house. Identifying and treating the source of his pain, therefore, may improve a senior pet’s behavior.
Blood, urine and stool testing on the senior pet will probably be requested as well. Such testing can uncover organ disease or infection that may contribute to an altered mental state or discomfort. Imaging studies such as radiographs (i.e., “x-rays”) or ultrasound may also be performed to evaluate for cancer, heart disease, spinal arthritis and other serious illness. Again, identifying and treating the underlying cause of a pet’s discomfort often improves his attitude.
If screening tests reveal no obvious abnormalities and all clinical signs point toward brain disease, several options are available. Just like puppies, senior pets with cognitive dysfunction may require special accommodations to keep them safe and comfortable. A number of medications are licensed to treat canine cognitive dysfunction. Moreover, dietary changes, certain natural supplements, environmental enrichment and behavior medication can also help protect brain function and slow decline.
As with Alzheimer’s disease in human loved ones, cognitive dysfunction syndrome can be scary, frustrating and sad for dog lovers. The good news is that intense research into brain aging continues to yield new and promising treatment options for people and pets alike.
Originally published in Pet Journal, April 2013