Cognitive Dysfunction in Dogs

Cognitive Dysfunction in Dogs

Dogs are living longer than ever before due to high-quality veterinary care and nutrition. Unfortunately, unique behavior problems can accompany increasing age. In one study, 28% of owners of dogs between 11 and 12 years of age reported at least one sign of cognitive dysfunction and 10% reported 2 or more signs. In 15-16-year-old dogs, 68% of dogs had at least one sign and 36% had two or more signs of cognitive dysfunction. Often, owners attribute their pet’s behavioral changes to old age and assume that nothing can be done to alter them.

Once the veterinarian and client have discussed the pet’s behavior changes, consideration of contributing medical diseases is essential. The signs of cognitive dysfunction are general and can be caused by medical diseases such as osteoarthritis, metabolic diseases, seizure disorders, neoplasia, and hearing or sight impairment. The primary signs of cognitive dysfunction in dogs are disorientation, interaction changes, sleep/activity changes, breakdown in housetraining, and changes in anxiety or aggression. It is important to isolate specific medical and behavioral diagnoses for each dog so that each problem can be treated appropriately.

Treatment for cognitive dysfunction is similar to other behavioral diagnoses and includes behavior modification, environmental modification, and often medication. Selegiline, a selective MAO-B inhibitor, is FDA approved for use in canine cognitive dysfunction. It can restore the sleep/wake cycle and help to slow the progression of cognitive dysfunction. Selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine (Prozac®) and sertraline (Zoloft®) can also be used to treat anxiety and aggression which may accompany cognitive dysfunction. Selegiline should never be combined with any drug which increases serotonin.

Nutritional therapy may also be indicated for dogs with signs of cognitive dysfunction. Canine b/dTM (Hills) diet has an antioxidant package that has been shown to improve age-related behavioral changes and learning ability in older dogs by limiting cellular damage in the brain. This diet can be helpful in prolonging normal cognitive function in older dogs. Owners could see a difference in as little as 30 days.

Nutraceuticals can be helpful in the treatment of cognitive dysfunction. Novifit® (Virbac) is a sam-E tosylate salt that has been shown in a double-blinded, placebo-controlled study to be effective in alleviating the signs of cognitive dysfunction. Zentonil Plus® (Vetoquinol), is another sam-E product that can support brain health and slow the progression of cognitive dysfunction.  Senilife® (Ceva) contains free radical scavengers, neuronal membrane stabilizers, and agents which increase blood flow. It has been shown to be effective in the treatment of CDS and works within 7 days. Supplements of any type should only be used after the dog has been evaluated by the veterinarian. Before adding anything to your pet’s diet or starting a medication, consult your pet’s veterinarian.

The general behavior modification treatment plan for dogs with cognitive dysfunction includes environmental enrichment, increased mental stimulation, structured interactions with the owners, institution of a predictable routine, and retraining certain behaviors. In addition, any other specific behavioral diagnoses should be treated. In order to make interactions more predictable, owners should use the dog’s verbal commands when communicating with him and alert him (with a word, sound, or light signal) when they are going to touch him. Older dogs may be startled easily due to visual, hearing, or orthopedic impairment causing them to act out aggressively or become fearful of everyday events. If the older dog is starting to act out aggressively, precautions should be taken to separate him from children or others who may instigate aggression while treatment is initiated.

Loss of housetraining is often of great concern to owners. Typically, the owners of dogs with cognitive dysfunction report that their dog goes outside for a walk and does not eliminate. After the walk, the dog immediately eliminates inside the home. In order to treat this problem, owners can re-housetrain the dog or train him to eliminate in a litterbox or on paper.

Confinement may be necessary when the older dog cannot be watched so that accidents do not occur. Ideally, older dogs would be confined in a small, tiled room with a bed and water. When this is not possible a crate can be used. For many older dogs, confinement at this stage of life can be very stressful.

An older dog may become the victim of aggression from a younger dog in the household, even if they got along previously. While this may be due to the younger dog’s inclination to rise in rank, it is more likely because the older dog is not offering appropriate social signals due to physical impairment. Often, the younger dog is confused by the lack of appropriate responses by the older dog. In situations like these, it is usually not helpful to “reinforce” or “elevate” one dog over the other because the problem does not lie with rank within the pack. Instead, inappropriate signaling and posturing between the two dogs or increased anxiety on the part of one or both dogs causes increased aggression.

As dogs live longer, the likelihood of age-related behavior problems increases. With the treatment of underlying medical problems and recognition and treatment of behavioral problems, the quality of life of our geriatric canine friends can be improved tremendously.