Cognitive Dysfunction Syndrome in Senior Dogs and Cats

What is cognitive dysfunction syndrome and how is it diagnosed?

Cognitive dysfunction syndrome (CDS) is a slowly progressive, age-related condition in which dogs and cats experience a reduction in cognitive ability and behavior changes that can affect their quality of life.

Diagnosis can be difficult. As animals age, their physical health naturally changes, which also changes their behavior. For example, a pet with arthritis may not get out of their comfortable bed to greet you. And a pet with kidney disease may not be able to hold their bladder and may urinate indoors. 

Your veterinarian will use certain consistent behavioral signs to identify CDS with near certainty. These signs are described in the next section. Your veterinarian may recommend some diagnostic tests to identify underlying health conditions that could be contributing to your pet’s behavior changes. 

Advanced imaging techniques such as MRI are sometimes used to screen for physical changes in the brain. The tests needed to diagnose CDS involve detailed examinations of the brain tissue and, to date, such tests are only available as postmortem studies.

At what age might cognitive decline begin?

Aging is an individual process that can be affected by physical illness, behavioral illness, genetics, and size (large dogs age more quickly than small ones). Experts recommend annual screening for CDS in dogs starting at 7 years of age, and starting in cats at 10 years of age.

Do pets get Alzheimer’s?

Dogs and cats develop brain changes and lesions similar to those found in people diagnosed with Alzheimer’s disease. Though the lesions are not identical, both Alzheimer’s disease and cognitive dysfunction syndrome are chronic, slowly progressive, and irreversible conditions.

What are the common signs of CDS in dogs?

The acronym DISHAA is a convenient way to remember the common signs associated with CDS in dogs. If your dog exhibits more than one of these signs, they may be experiencing more than just routine aging and should have a physical and behavioral evaluation.

DISHAA refers to the following:

• D: Disorientation. Dogs become lost in familiar areas, fail to easily find their food or water dish, attempt to pass through the wrong side of a doorway, or are unable to recognize familiar people.
• I: Interactions (Social). Dogs show changes in how they interact with familiar people and pets. They may become more clingy and demanding or might become reclusive.
• S: Sleep-Wake Cycle. Dogs sleep more during the day and then become restless, often pacing during the night.
• H: House Soiling, Learning, and Memory. House-trained dogs may soil in unusual or undesirable locations. They may forget to eliminate while outdoors and then do so as soon as they return to the house. They may not respond to previously learned behavioral cues. They may not adjust to changes, such as new schedules, as quickly as when they were younger.
• A: Activity Level. Dogs may show a reduced interest in play. They may rest more or may wander or pace. 
• A: Anxiety. Dogs may become frightened of new stimuli or develop phobias related to specific sounds, such as thunder. Some dogs become uncomfortable when left home alone (separation-related distress).

What are the common signs of CDS in cats?

The acronym VISHDAAL is used to remember the common signs of cognitive dysfunction syndrome in cats, in order from most common (V) to least common (L). Each of these signs can and often does relate to a physical illness. Be sure to consult with your veterinarian if your cat exhibits any signs of VISHDAAL.

VISHDAAL refers to the following:

• V: Vocalization. Cats may vocalize in a demanding or mournful way, especially overnight.
• I:  Interactions (Social). Cats may be more demanding, avoidant, or aggressive.
• S: Sleep-Wake Cycle. Cats may sleep more during the day and awaken during the night, often pacing and yowling. 
• H: House Soiling. Cats eliminate outside their litter box.
• D: Disorientation. Cats may get “stuck” in a location and seem unable to navigate. 
• A: Activity level. Cats become less playful and may pace. They may groom themselves less.
• A: Anxiety. Cats may become easily agitated or may be fearful of familiar noises.
• L: Learning. Cats may not respond to cues such as their name. They may not adjust to a new schedule or routine.

Can behavior problems in senior pets be treated?

In many cases, yes, behavior problems in senior pets can be treated. The first step in treating a pet, regardless of age, is to have a full medical and behavioral assessment. The diagnosis will guide the treatment of both the underlying medical conditions and the behavioral conditions. Treatment of behavioral conditions for pets of any age typically includes adjustments to the environment, behavior modification and, in some cases, psychotropic medication.

You may need to continue aspects of the behavioral treatment program even when medical conditions are well controlled. For example, medical conditions that trigger an increase in thirst may require you to continue to take your dog out to eliminate more often or provide an indoor toilet area; otherwise, house soiling may persist. Aging cats that eliminate more frequently may need you to continue to provide easily accessible litter boxes to ensure that they always have a clean box.

Can medications or dietary products slow the progress of brain aging?

Several products have been developed to slow the progression of cognitive changes or reduce the intensity of signs. Since the disease is still not fully understood, a wide range of treatment strategies and medications have been tested, with some showing more promise than others.

There is one medication currently licensed for treatment of cognitive decline in dogs in North America: selegiline (Anipryl® Pfizer Animal Health). Your veterinarian will consider your pet’s specific behavioral signs as well as any ongoing physical illnesses and current medications before prescribing any medication, including medications specifically meant for CDS. Treatment of senior pets requires a balanced approach to avoid undesirable side effects.

Nutraceuticals are food-based products that may slow brain aging and reduce signs of cognitive dysfunction, although research is limited. Products include Denamarin®, Denosyl®, and Novifit® which contain SAMe, and Senilife®, which contains Ginkgo biloba, phosphatidylserine, and a combination of antioxidants. Ask your veterinarian whether these or other available products might be helpful and safe for your pet.

Diets enriched with antioxidants may be beneficial for maintaining brain health. For dogs, commercially designed products include Hill’s Prescription Diet Brain Care + j/d, Purina NeuroCare, and Purina Pro Plan Bright Mind. Before making any diet changes, consult with your veterinarian. Nutrition is complicated, and a diet must be compatible with all your pet’s health conditions. Your veterinarian may even suggest a consultation with a nutritionist to discuss the proper balance of protein, fiber, fat, and other nutrients for your pet. Most importantly, especially for cats, your pet must love it.

Finally, anxiety and frustration can exacerbate cognitive ability. Your veterinarian may refer you to a veterinary behaviorist who understands the physical and emotional components associated with aging. A veterinary behaviorist can treat multiple behavioral conditions that are happening at the same time and can provide behavioral and environmental modification to address the signs of CDS specific to your pet.

How can I help my pet live a longer and healthier life?

Environmental enrichment helps maintain brain health (“use it or lose it”). Spend time every day practicing old tricks and training new ones. Puzzle toys may also be used to help your pet “think.” Consider creating scavenger hunts so your pet can use their nose to find snacks or new toys. Be sure your pet appears to be enjoying the enrichment you provide.

Play and physical exercise are also important for brain health. Your veterinarian can help you design an exercise program that is safe and suitable for your dog or cat. Be sure to monitor your pet’s weight – being overweight has a negative effect on the brain and body.

How can I help my pet live happily in their senior years?

With a few adjustments to your routines and your house, you can easily improve your senior pet’s golden years.

• Senior pets may need more frequent access to appropriate bathroom areas. Dogs benefit from more frequent trips outside or access to a suitable indoor potty area. Be sure your cat has a clean litter box that is easy to access. 
• Some cats are less flexible as they age, so consider providing an extra-large litter box with low sides and ample room to turn around.
• If your floors are slippery, use runners or floor coverings to provide traction. 
• If your dog or cat enjoys sharing furniture with you, provide a ramp or portable steps to allow them to climb up. 
• When pets begin to lose vision, they benefit from additional lighting or aroma cues to help them navigate the home. 
• Most importantly, continue to find ways to do things you and your pet enjoy doing together — especially play.