Sundowning: Here's What to Expect in Your Aging Pet

Today, advances in veterinary care mean our cats and dogs live longer, healthier lives than ever before. And just like in people, aging brains means some memory loss. But a percentage of old dogs and senior cats develop more severe signs of dementia, or cognitive dysfunction. These pets suffer from a condition that mirrors some aspects of human Alzheimer's disease, including behaviors described as "sundowning."

Signs of Sundowning

Signs of cat and dog cognitive dysfunction can be vague and confusing, and many of these symptoms mimic other disease conditions. Common issues fall under five broad categories listed in the acronym "DISHA." Look for the following: disorientation, interaction changes, sleep changes, housetraining issues, and anxiety or compulsive behaviors. Disorientation means your pet wanders aimlessly, acts lost and confused, may not recognize family members or other familiar people and places, and gets "stuck" in corners or lost in the house. Interaction changes refers to behaviors such as your pet no longer greeting family members, dislikes or avoids petting, is not as interested in getting attention, and displays interaction changes with other pets. In terms of sleep changes, look for signs such as your pet being awake and active at night, meaning that sleep cycles are disrupted or reversed. Another sign is that housetraining has been forgotten—dogs forget to ask to go out and cats can't find their litter box. Last, looking for anxiety or compulsive behaviors. Your pet may show tremors, howling, repetitive pacing, licking the floor or other objects, circling, or tail chasing.

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When a Pet Might Develop Sundowning

Dr. Benjamin Hart, a veterinary behaviorist and Professor Emeritus at University of California-Davis, says that canine cognitive disorder has long been recognized. He explains that dogs, similarly to people suffering from Alzheimer's disease, develop a beta amyloid pathology in the brain. This is a starch-like protein that becomes waxy once deposited in the tissues. Thirty percent of dogs aged 11 to 12 had one or more symptom. Sixty-eight percent of the 15 to 16-year-old dogs had one or more symptom.

More recently, the condition has also been recognized in cats. "You're more likely to see it in 15-year-old and older cats," says Gary Landsberg, DVM, a veterinary behaviorist in Thornhill, Ontario. He authored one of the first research papers on cats that concluded, in part, that as many as 80 percent of cats he sees that are over the age of 16 show signs of senility. Like affected humans and dogs, cats with cognitive dysfunction also have deposits of amyloid material in the brain.

Diagnosing Cognitive Dysfunction

It's important to diagnose cognitive dysfunction correctly. Behavior changes in your aging pet often have other causes. A break in housetraining might be due to kidney disease or diabetes. An old cat's yowls could be due to age-related deafness, or hypertension. Disorientation and personality changes could also point to a brain tumor or neurological disruptions from liver disease. Diagnosis relies on eliminating other causes. According to a report by Washington State University Veterinary Teaching Hospital, veterinarians believe as many as 85 percent of pets suffering with age-related senility are never diagnosed. Sadly, many are euthanized when behaviors become unacceptable.

How You Can Help Your Sundowning Pet

There are veterinary prescriptions, over-the-counter diets, and pet supplements that may offer a reprieve. Memory games also help, as well as maintaining routine, reducing stress, and enriching the environment perhaps with a special bed for your aging dog. The human medicine selegiline hydrochloride (Anipryl) has been FDA-approved to treat canine cognitive disorder. Anipryl may work to prevent ongoing damage to the brain. It acts on one of the neurotransmitters responsible for nerve-to-nerve communication and slows the natural destruction of the chemical compound dopamine in the brain. Dr. Landsberg says the medicine works very well in about one third of cases, nominally well in another one third, and not at all in the final percentage of dogs. Although not FDA-approved for cats, it has been used off-label with some success in aging felines, too. Pets need to be on the drug for about four weeks before any results can be expected.

A natural component of some foods—called phospholipids—can help reverse signs of cognitive disorders by helping brain cells send and receive nerve impulses more effectively. Choline and phosphatidylcholine, two common message-sending compounds, are found in a dietary supplement called Cholodin, which is a less expensive alternative to Anipryl. The products are available through your veterinarian and come in a pill form or powder to be mixed into the food.

Some specialized therapeutic diets are now available that also help temporarily reverse brain aging changes. Diets containing alternative energy sources such as fatty acids from medium-chain triglycerides (MCTs) may prove beneficial in offsetting cognitive decline. Hemp supplement products also may help dogs—however, they must avoid the potential toxic components of the herb found in some human products. Hemp can be used to aid in decreasing the severity of dementia. Ask your veterinarian if this supplement may benefit your pet.

As with humans, it's important to keep dogs active and mentally engaged. That can help slow or even prevent some of the "brain rust" that slows down cognitive abilities. Teach tricks and practice obedience drills and offer interactive puzzle toys. That exercises not only his body, but his mind, and preserves the bond of love you've developed together. The old saying, "use it or lose it!" applies equally to cat brains. Offer stimulating views such as bird feeders outside windows. Teach your cat tricks, or to walk on a leash. And offer puzzle toys that reward the cat's interest by dispensing food. This can mimic feline hunting behaviors and keep the cat entertained and mentally sharp. These options work best in combination, but still offer only a temporary fix, not a cure. Reversing the signs for months or a year or more is priceless when it extends your beloved pet's life.