Dog Dementia (Cognitive Dysfunction): Signs and How to Help

What is dog dementia?

Canine cognitive dysfunction is a chronic, progressive brain disease linked to aging. The brain slowly shrinks, and abnormal proteins and inflammation build up in it. These changes have been compared to Alzheimer's disease in people. As the disease progresses, it affects memory, learning, awareness of surroundings, sleep and behavior.

It is more common than many owners think. In one US study of dogs aged 11 to 16, owners reported signs of cognitive impairment in 28 percent of dogs aged 11 to 12 and in 68 percent of dogs aged 15 to 16. An Australian survey of dogs aged 8 and older estimated that about 14 percent had the condition, yet only about 2 percent had been diagnosed by a vet. Many owners assume the changes are just old age and never mention them.

Age is the strongest risk factor. A large study of more than 15,000 dogs in the Dog Aging Project found that the odds of cognitive dysfunction rose by about 52 percent with each extra year of age. Among dogs of the same age and health, those described as not active had much higher odds than very active dogs. That study shows a link, not proof that exercise prevents dementia, but it is one more reason to keep older dogs moving.

Signs of dog dementia: the DISHAA checklist

Vets often group the signs under the letters DISHAA. Changes usually start small and build slowly over months.

• Disorientation. Getting lost in familiar rooms or the yard, going to the wrong side of a door, getting stuck behind furniture or in corners, or staring at walls or into space.
• Interaction changes. Becoming clingy and needy, or withdrawn and less interested in people and other pets. Some dogs no longer seem to recognize familiar people, and some become irritable.
• Sleep-wake changes. Sleeping more in the day and waking at night, pacing, whining or barking in the night. Some dogs get more restless in the late afternoon or evening.
• House soiling. Accidents indoors in a dog that was reliably house trained, sometimes even in its own bed, or forgetting to ask to go out.
• Activity changes. Less interest in play, walks or toys, or the opposite: aimless wandering, pacing, repetitive licking.
• Anxiety. New fears of noises, people or going outside, distress when left alone, or general restlessness.

Learning and memory are also affected. Your dog may respond more slowly to its name or to cues it has known for years, and it may find new things harder to learn.

Researchers who followed older dogs in Denmark found that the condition progresses at a different pace in each dog. In their study, a third of dogs with normal cognition developed mild impairment within two years, and some dogs with mild impairment went on to full cognitive dysfunction. Spotting the early, mild signs gives you the best chance to slow things down.

Other problems that can look like dementia

Many illnesses in older dogs cause similar changes, and some are very treatable. That is why dementia is diagnosed only after other causes have been checked. Conditions that can look like dementia include these.

• Pain from arthritis or dental disease, which can cause restlessness, irritability and accidents. See our guide to arthritis in dogs.
• Loss of vision or hearing, which can make a dog seem confused or startled
• Hormone problems, such as hypothyroidism, Cushing's disease and diabetes
• Urinary tract infections, kidney or liver disease, and urinary incontinence
• High blood pressure, brain tumors and other neurological disease
• Side effects of medicines

A dog can have dementia and one of these problems at the same time. Treating the other problem often makes the dementia signs milder too.

How vets diagnose it

There is no single test for dog dementia. Your vet will ask detailed questions about the changes you have seen and how they developed. A physical, orthopedic and neurological exam, blood and urine tests and sometimes blood pressure checks help rule out other causes. Recent international guidelines describe the diagnosis as resting on a history of slowly progressive DISHAA signs, no other explanation found on examination and tests, and signs that persist after other problems have been treated. In some cases, an MRI scan of the brain can show the shrinkage typical of the disease.

Before the visit, write down what you have noticed and when it happens. Short videos of night pacing, getting stuck or staring are very helpful, because dogs often behave normally in the clinic. Many vets use a questionnaire to score the signs, and repeating it every few months shows whether treatment is working.

How to help: treatment and care

Dementia cannot be reversed, but a combination of approaches can ease the signs and improve daily life. It is worth starting as soon as you notice changes.

Medication. Your vet may prescribe selegiline, a medicine used to manage the signs of cognitive dysfunction in dogs. Some dogs also benefit from medicines that ease anxiety or help them sleep at night. Your vet will choose a medicine and a dose for your dog and check how it responds. Never give your dog human sleep aids or supplements without asking your vet, since some are harmful to dogs.

Diet. Diets designed for brain aging contain extra antioxidants, omega-3 fatty acids and other nutrients. One controlled study of 87 dogs with signs of cognitive dysfunction found that a diet with medium-chain triglycerides and a blend of brain-supporting nutrients improved all six groups of signs over 90 days. Evidence is still growing, so ask your vet whether a therapeutic diet or supplement suits your dog.

Mental and physical activity. Keep your dog's brain and body busy, adjusted to what it can manage. Short, gentle walks, sniffing walks where your dog sets the pace, food puzzle toys, easy training games with treats and gentle play all help. Even a few minutes a day is worthwhile.

Routine. Dogs with dementia cope best when life is predictable. Feed, walk and go to bed at the same times every day. Keep furniture where it is, and avoid big changes in the home when you can.

Practical tips at home

• Night waking. Keep a short log of when your dog wakes and what seems to trigger it. Give more activity during the day and early evening, and offer a toilet trip just before bed. If nights stay disturbed, talk to your vet about medication.
• House soiling. Go back to puppy-style training: frequent trips outside, rewards for going in the right place and close supervision indoors. Pee pads or an indoor toilet area can help. Our guide to house training explains the basics.
• Safety. Block stairs and pools with baby gates, and pad sharp corners if your dog keeps bumping into them. Make sure your dog's collar tag and microchip details are up to date, since confused dogs can wander off.
• Anxiety. Do not punish accidents, barking or clinginess, because this increases anxiety. Avoid shutting a dog in a crate if it is not already used to one, since confinement can itself cause panic.
• Comfort. Give your dog a soft bed in a quiet spot near the family, and use non-slip rugs on smooth floors.

Our guide to caring for a senior dog has more ideas for keeping older dogs healthy and comfortable.

When to see a vet

Book a vet visit if your older dog shows any of the DISHAA signs above, even if they seem mild, so that a plan can start while the signs are still mild. Contact your vet the same day, or an emergency clinic out of hours, if you notice any of these signs.

• Sudden confusion, collapse or loss of balance
• A seizure, a head tilt, walking in circles or pressing the head against a wall
• Sudden blindness, or eyes moving rapidly from side to side
• Straining to pee, passing blood, or not peeing at all
• Refusing food or water for more than a day, or repeated vomiting
• Crying out in pain, or panting and pacing that will not settle

Dementia comes on slowly. A sudden change in behavior is more likely to be another illness, such as a stroke, a brain problem, an infection or pain, and it needs prompt attention.

Living well with an older dog

In a Danish study, dogs diagnosed with cognitive dysfunction did not die sooner than other older dogs. Many live for years with good care. In time, though, the signs can become severe and distressing for the dog. If you are unsure whether your dog still enjoys life, our guide on quality of life and saying goodbye may help you think it through with your vet.

Older rescue dogs are easy to overlook, yet many have years of love left to give. At Paw Squadron, every rescued dog sees a vet and is dewormed after rescue, whatever its age. If you are thinking about giving an older dog a home, see who is waiting on our Adopt page.

For more guides on senior dog health, browse PawPedia, or write to us from the Contact page.