Devoted to More Wags and Purrs.

CDS: Dog and Cat Alzheimer’s


Cognitive Dysfunction Syndrome is disease many pet owners accidentally ignore. The symptoms begin subtlety, and progress slowly. Often people mistake this disease for “just getting old,” and miss the opportunity to manage this serious problem.

Cognitive Dysfunction Syndrome, or CDS, is a form of dementia in older dogs and cats, similar to Alzheimer's in people. Early symptoms seem like frustrating behavioral problems, and often include a loss of house-training or litter-box training, nighttime restlessness and noisiness, and a decreased reaction to stimuli. Many pet owners confuse the early stages of this disease with a hearing loss, since their pets seem less reactive to noises. They mistake the house-training problems to “being old” or just spite. As the disease progresses, the sleep-wake cycle becomes more disturbed, with some pets sleeping most of the day and being awake, often barking, yowling and whining, during the night. They may forget their normal routine, expecting meals at random times and then not eating at meal times. Some pets become exceptionally clingy with their owners, while others become more withdrawn and distant.


These symptoms are not specific only for CDS. Night time vocalization in cats also occurs with a hyperthyroidism, caused by benign thyroid tumors. Problems with blood pressure or other brain disease can mimic the symptoms of CDS as well.


The end stages of CDS are disheartening; pets may become lost in their own house. One of the classic symptoms in dogs is to go to the wrong door, staring at a closet thinking it leads outside, or looking at the hinge side of a door and expecting it to open. Some pets will get “trapped” in corners or behind furniture, and will not be able to figure out how to back up and get out. Affected dogs and cats may lose the ability to recognize their owners or housemates, and maybe become scared of these “strangers”


The cause of this brain malfunction is similar, but not exactly, like a human with Alzheimer's. A protein known as beta-amyloid builds up in the brain and prevents the neurons, or brain cells, from communicating properly. Neurotransmitters, which are the chemical signals these neurons use to communicate, are lessened as well. The exact causes of this changes is not known.


There are several different ways to manage and treat CDS. High levels of powerful antioxidants have been shown to reverse some of the symptoms. Hill’s Science Diet has developed a food called B/D (Brain Diet) that helps as well. Anipryl (selegiline) has been approved by the FDA to treat CDS in dogs, and some other drugs may help as well. As with people with dementia, environmental enrichment and “exercising” the brain may also be of use.


Cognitive dysfunction can be a truly disheartening disease. No pet owner wants to see their four legged friend fade away into confusion and dementia, Early intervention can help, but pet owners should watch for the symptoms, and not just assume their pets are “getting old.”

 Michael J. Rumore D.V.M.