What is Cognitive Dysfunction Syndrome?

Researchers believe Cognitive Dysfunction Syndrome (CDS) is caused by physical and chemical changes that affect the brain function in older dogs. Dogs with CDS may show signs of confusion and/or various other behavioral changes that are not a normal part of aging.

This confusion can lead to a life of lonely isolation, separated from family members who have come to cherish their older dog's companionship. This can be as hard on family members as it is on the dog. Pet owners often describe their dogs as less responsive, forgetful or confused.

In one study at the University of California-Davis, 62% of 11- to 16-year-old dogs showed signs in at least one category of CDS.^1,2 In a pet owner survey, nearly half of dogs age 8 and older showed at least one sign associated with CDS.³

References:

1. Neilson JC, Hart BL, Ruehl WW: Cited in Hart BL, Hart LA: Selecting, raising and caring for dogs to avoid problem aggression. JAVMA, 210(8):1129-1134; 1997.
2. Ruehl WW, Hart BL: Canine Cognitive Dysfunction. In Psychopharmacology of Animal Behavior Disorders (Dodman NH, Schuster L, eds.). Boston: Blackwell Scientific, 1998; pp. 283-304.
3. Proprietary market research, 1998. Pet owner sample size: 255. Data on file, Pfizer Animal Health.