Pet Health: Dog Alzheimer’s
Dr. Fiona is a guest veterinarian blogger for pet insurance provider, Pets Best.
It is an unfortunate fact that our pets age faster than we do. Even with pet insurance and the best care, Fido will likely reach his or her senior years before you, or will eventually surpass you.
In addition to common medical problems such as dental disease and arthritis, canine cognitive dysfunction is also a common occurrence in senior dogs. Recognizing its symptoms can allow you to help your dog to age gracefully.
Dementia is taken from the Latin roots ‘de’ meaning without, and ‘ment’ meaning mind, literally a lack of mind. Older dogs and cats, for that matter, can absolutely suffer from this debilitating syndrome just like older people. The accepted term in veterinary medicine is Canine Cognitive Dysfunction Syndrome, or CDS. It refers to the gradual onset of behavioral changes that cannot be explained by other illness, medical conditions, or sensory or motor impairment. Many experts liken the disease to Alzheimer’s disease in people.
The progression of clinical signs can be so gradual that often owners don’t recognize it is happening. The many behavior changes that manifest in this disease include disorientation and confusion; pets will wander, stare, or get ‘lost’ in familiar places. There may be a change in learning, or a change in previously learned behaviors, such as being house trained; a dog with CDS might start house soiling. There may be a change in your pet’s activity, s/he might be much less active, or might engage in repetitive behaviors like barking. There may be a change in sleeping patterns, including restlessness and irritability. There may be a decrease in your dog’s responsiveness to your voice, or other stimuli, which can appear as ‘selective hearing.’
Many older dogs suffer from this syndrome. Some studies suggest two thirds of dogs over the age of 11 show at least one sign of CDS. About half of owners with dogs older than 8 reported their dogs showed at least one clinical sign of CDS in one survey by Pfizer animal health. Only 17% reported these to their veterinarian. There have been no differences in susceptibility and dogs seem equally affected regardless of breed or whether they are spayed or neutered.
The reason behind CDS isn’t precisely understood, but we know that the brain atrophies, just like an unused muscle, as the animal ages. Research has demonstrated the formation of plaques, made up of a neurotoxic protein, can form in an older animal’s brain. This seems to compromise the brain’s function. In addition, neurotransmitters are altered during aging, making them less effective.
There are some things you can do to help prevent this disease from occurring, and even to help reverse some of the clinical signs as they occur. Be mindful of these changes; report them to your veterinarian. Enrich your older dog’s environment by providing new toys and play games with them. You might add a younger dog to the household to keep your older dog active. Take the dog new places and encourage them to be social. In one laboratory study, environmental enrichment over a two year period was demonstrated to be an effective tool for learning tasks.
There has been some promise of certain prescription medications, as well as a diet rich in antioxidants for helping pets with CDS. If you are concerned that your dog might be suffering from doggie Alzheimer’s, or if you have any other questions for your veterinarian, contact him or her for more information.