Cognitive dysfunction syndrome (CDS) is essentially the dog equivalent of Alzheimer’s disease. With CDS, a dog’s brain gradually degenerates, leading to abnormal and senile behaviors that reflect declining cognitive function. CDS is common in older dogs, generally occurring after nine years of age.
As my patients age, some changes naturally occur. One of them is a slow progressive set of symptoms called Cognitive Dysfunction Syndrome (CDS). One of the most distressing symptoms that occur in older pets is urinating and defecating in the house. While this can be attributed to CDS, other conditions cause this also.
Other symptoms that occur in the geriatric pet and are attributed to CDS include aimless wandering and vocalization. Unfortunately, there is no cure for this, and even palliative measures are often unsuccessful.
However, some disease syndromes mimic these signs. Increased urination can be caused by drinking more water. An increase in water consumption can be caused by kidney disease, diabetes, or adrenal gland disease. When tests for these conditions prove negative, we can attribute them to (CDS). If positive, some treatments can alleviate the condition. In the case of inappropriate urination, can also be caused by a weakening of the muscle that controls urination in the neck of the bladder. This can be improved by hormonal supplementation drugs
CDS is caused by age-related changes to the brain. In dogs with CDS, a substance toxic to the brain called “beta-amyloid protein” accumulates. Other changes in the brain include reduced blood flow and dysfunctional neurons. Neurons are the cells that carry information throughout the brain and body. When neurons don’t function correctly, the brain’s ability to remember, process information, and tell the body what to do is impaired.
Cognitive enrichment may improve your dog’s brain function. Cognitive enrichment consists of exercise, social interactions, providing new toys, and teaching new commands to your dog.
Signs of CDS an owner may recognize include:
To diagnose CDS, I rely on the information given to me by the owner, the dog’s symptoms, and physical exam findings. To rule out other causes of the dog’s symptoms, I may use additional tools such as blood and urine tests. An MRI may be done to look for abnormalities in the dog’s brain at a referral hospital if so desired.
There is no cure for canine CDS. However, there are a number of treatments that may slow the progression of the disease and relieve some of the dog’s symptoms. Since CDS a diagnosis of exclusion, it's always possible that cognitive dysfunction is both under-diagnosed and over-diagnosed. For instance, some dogs with symptoms of cognitive dysfunction will improve markedly with great dental work and pain medication.
Treatments for CDS include:
Dietary changes: your dog may be put on a specific therapeutic diet designed to help. These diets contain ingredients such as antioxidants, fats, and fatty acids that may protect and promote healthy brain cells.
Dietary supplements: your veterinarian may recommend dietary supplements such as Senilife®, which is rich in antioxidants, or oils rich in a type of fat called “medium-chain triglycerides.” Medium-chain triglycerides provide energy to the dog’s brain, which is helpful because the brain is less able to use glucose for energy in CDS.
Drugs: your veterinarian may recommend medications that could improve your dog’s cognitive function. These include MAO inhibitors such as Anipryl, which may help neurons communicate with each other and protect the brain from damage. Drugs such as propentofylline, which is licensed for use in some countries in Europe, increase blood flow in the brain and may help dogs with CDS.
Some veterinarians may suggest trying herbal therapies and acupuncture. These methods have the potential to help affected dogs, but they have not been well-studied in dogs with CDS.
As there is no cure for canine CDS, the disease will progress. However, if CDS is caught early and treated effectively, the dog could live a full, quality lifespan. Unfortunately, dogs with severe cases of CDS generally have a worse outcome. If you notice signs of CDS in your dog, it's best not just to attribute them to old age; see your veterinarian.