by Katherine Tolford
While your beloved senior dog can’t really forget where he put his car keys, it turns out that he is capable of experiencing “senior moments.” If your dog forgets the route on your daily walk or if he’s not enjoying the things he once did, like chasing after his favorite toy or greeting you at the door, he could be suffering from canine cognitive dysfunction (CCD), or the doggy version of Alzheimer’s.
Canine cognitive dysfunction can occur for a number of reasons, like an accumulation of abnormal proteins in the brain. This creates a build-up of plaque, which eventually damages nerves and results in the loss of brain function, which can affect your dog's memory, motor functions and learned behaviors.
Most dogs, regardless of breed, experience some form of CCD as they age. In a study conducted by the Behavior Clinic at the University of California at Davis, researchers found that 28 percent of dogs aged 11-12 years, and 68 percent of dogs aged 15-16 years, showed one or more signs of cognitive impairment.
Dr. Bonnie Beaver, a board-certified veterinary behaviorist, says a lot of dog owners aren’t aware that their dogs can suffer from CCD until they take them to the vet for what they think are physical or behavioral problems.
“The first thing you should do is to talk to your vet to make sure that it’s cognitive dysfunction and not something else. It comes on gradually and owners don't always notice things,” says Dr. Beaver.
“What did your dog stop doing that he used to do? Is he not chasing his ball because he has arthritis? Or is it that he doesn't care anymore? It's important to differentiate between physical and mental causes."
Some symptoms of CCD can overlap with other age related conditions, such as arthritis, diabetes, cancer, and kidney issues, as well as hearing and sight loss. Depending on your dog's symptoms your vet may propose x-rays, blood tests,urinalysis, or other diagnostic tests.
Dr. Denise Petryk, a former emergency room vet who now works with Trupanion pet insurance, says the widely accepted DISHA acronym can help dog owners characterize the most distinct signs and changes associated with CCD.
The term DISHA refers to the symptoms Disorientation, [altered] Interactions with their family members or other pets, Sleep-wake cycle changes, House soiling, and Activity level changes.
“It gives us the ability to check against a list of things to show that something else isn’t going on. If your dog has one of the symptoms or some combination then we’re more likely to call it cognitive dysfunction.”
Dr. Beaver says to keep in mind that there isn’t necessarily a progression to the symptoms your dog may be experiencing.
“The more signs and frequency we see, the greater significance of the problem. Each sign or symptom doesn’t really signify a particular phase,” she says.
Here’s the DISHA list of possible symptoms that may demonstrate cognitive dysfunction in dogs:
One of the most common things pet parents may notice is that their senior dog gets disoriented even when he’s in his normal or familiar environment.
“This often happens when the dog is out in the backyard and he goes to the wrong door or the wrong side of the door to get back in. The part of the brain that is involved with orientation has been affected.” Beaver says.
Your dog may also experience difficulty with spatial awareness. He may wander behind the couch and then realize he doesn’t know where he is or how to get out.
At bedtime you may find your dog in a different part of the house staring at the wall instead of curled up in his dog bed. Petryk says dogs have a good sense of timing, so this is a sign that something is wrong.
“The first thing you should do is to take your dog in for a check-up. It might not be a cognitive issue, so your vet may want to rule out some other possible medical causes which could involve a brain tumor or diabetes.”
Canine cognitive dysfunction can affect your dog’s interactions with people and other animals. Your once sociable dog who used to be the most popular pooch on the block now acts cranky and irritable, or even growls at other animals or children. He may lash out and bite his once favorite playmates. Petryk cautions that this behavior could be the result of something serious.
“He may be acting this way because he’s in pain. He could have arthritis or some other ailment that hurts when he moves or is touched. Your vet may want to do x-rays to rule out a painful condition.”
Some dogs withdraw from their family and their favorite activities. They may fail to notice when the doorbell rings and seem disinterested in greeting visitors, or they may stop barking at the mailman. Your dog may not even respond when you get his leash out to go for a walk.
"I've had patients whose dogs don't recognize that their favorite cookies are treats for them, “ says Petryk. “The owner's first instinct is to buy other cookies. They don't realize something else could be going on.”
Sleep-Wake Cycle Changes
A change in sleep patterns or a disruption in circadian rhythms is one of the more specific symptoms related to cognitive dysfunction. Dogs that used to sleep soundly may now pace all night. Many dogs reverse their normal schedules, so their daytime activities become their nighttime activities. This “up all night” routine can be frustrating and tiring to pet owners.
“If your dog is active at night and you want to get him to sleep, a nightlight or white noise may help him,” Beaver says.
If this doesn’t provide relief, consult your vet for medications that may ease your dog’s anxiety and reestablish normal sleep cycles.
Urinating or defecating in the house is one of the most common ways cognitive dysfunction is detected in dogs, especially if the dog was previously housetrained.
Petryk says that when this happens it’s important for owners to consider that their dog may have lost its ability to voluntarily control elimination or even let them know that he needs to go outside.
“After we run tests and rule out a bladder infection, kidney problems, or diabetes, then there’s usually been a cognitive change. If your dog is staring out at the sliding glass door and then poops in the house anyway and it’s not because of bowel trouble, then he’s lost the understanding that he should poop outside,” Petryk explains.
Dogs with cognitive dysfunction may show a decreased desire to explore and a decreased response to things, people, and sounds in their environments. They may not greet you or they may no longer respond on cue to fetch their favorite toy. They may also be less focused and show an altered response to stimuli. Some dogs have trouble eating or drinking or finding their food bowls.
"They may drop something when they’re eating and they can’t find it,” says Petryk. “If they don’t have sight or hearing issues, this can be a true indication that they are experiencing cognitive dysfunction.”
Although older dogs experience a normal decline in activity levels, they may also experience restless or repetitive locomotion.
"They may exhibit repetitive motion; things like head bobbing, leg shaking, or pacing in circles. This kind of action is more related to cognitive dysfunction or a degeneration of the brain. It’s less likely to be mistaken for anything else," Petryk says.
Owners should also be aware if their typically quiet dog now barks excessively or if he barks at times when nothing is going on.
Diet, Medication, and Environment
Watching your dog lose his cognitive abilities can be a difficult and disturbing process, but there are things you can do to help ease his discomfort.
“You can’t stop the process but it’s possible to slow it down so they don’t go from one problem to three problems,” Beaver says.
Certain dog foods are formulated to help slow down cognitive dysfunction and include anti-oxidants and omega-3 fatty acids to promote and strengthen cell health.
Beaver says combining an enhanced diet with efforts to enrich your dog’s environment provides the greatest chance for cognitive improvement.
“Introducing things like food puzzles encourages mental stimulation,” she explains. “Any type of food dispenser toy where they have to roll it around to get the food out helps keep them mentally active.”
Regular scheduled play sessions can also stimulate your dog’s brain and improve his learning and memory abilities.
“If your dog doesn’t have physical restrictions, grab his leash and take him to the dog park where he can socialize with other dogs,” says Petryk. “It’s possible to slow deterioration by keeping him physically and mentally active, just like it is for us.”
Psychoactive drugs and dietary supplements can also help slow your dog's decline, but Beaver recommends visiting your vet for specific recommendations that can be tailored to your dog’s health and medical history.
“If, for instance, your dog also has a heart problem, the medications he takes for that is going to factor into any medications prescribed for cognitive decline,” says Beaver. “Vets and owners need to work together to establish a plan.”
“As your dog gets older he should be having twice yearly check-ups. That way they can help differentiate between normal aging and what's pathological or wrong,” says Petryk.
She suggests going into the vet with a list of questions and observations—things that you notice when you’re at home. If changes happen gradually, it’s easy to overlook them, says Petryk.
“People can be blind to the changes in their pets because they’ve happened slowly,” she says. “They may not notice things and it may be too late to fix them.”