Q&A with a Vet: What is Cognitive Dysfunction in Dogs and Cats?
Pets can develop neurological diseases that affect their brain function.
Cognitive Dysfunction Syndrome (CDS) can occur in both dogs and cats. This is a condition best described in geriatric dogs and is similar to Alzheimer’s disease in people. In veterinary and human patients, there is no known underlying cause that has been identified to explain why this condition develops.
However, there are some consistent microscopic changes in affected patients of each species, most notably beta-amyloid plaque formation. Most affected dogs and cats are of geriatric age (dogs older than nine years and cats older than 12 years).
There has not been an identified predisposition for this condition including breed or medical history. Onset and progression tend to be insidious in nature and primarily the result of cognitive impairment.
Symptoms include:
altered sleep/wake cycle (sometimes called “sundowners” syndrome)
inattentiveness
pacing
demented behavior
becoming lost in a familiar environment
failure to recognize familiar individuals
fecal and urinary accidents
hearing loss
excessive vocalization
other anxious behaviors
Diagnosis is typically achieved based primarily on historical complaints of progressive cognitive impairment. MRI of the brain is often also used to evaluate for evidence of cerebrocortical and intrathalamic adhesion atrophy +/- beta-amyloid plaques to help support diagnosis, although some of these MRI changes can be seen in the aged brain of dogs without CDS.
There is mixed evidence regarding treatment efficacy including drugs, diet, and supplements. The most frequently referenced treatment option for dogs and cats is a drug called L-deprenyl (selegiline) as there is research to suggest it can improve cognitive function and delay the progression of CDS. Unfortunately, there is a drastically variable response to this drug, and some patients show no response at all.
Additionally, other drugs and supplements have been used to counteract some of the symptoms in these patients such as trazodone or fluoxetine to treat anxiety and improve the sleep-wake cycle, pacing, vocalizing, and delirium. Supplements such as melatonin, valerian root, and dog-appeasing pheromones have been used - again, with variable responses in the CDS patient population as a whole.
Other treatment strategies include environmental enrichment including regular exercise and frequent introduction to new toys. Owners should seek veterinary consultation at the onset of an altered sleep-wake cycle, demented/anxious behavior, or fecal and urinary incontinence so that symptomatic treatments can be initiated as these are the symptoms that seem to pose the most significant barrier to quality of life for most CDS patients and their owners.
The prognosis for CDS is guarded, there is frequently subtle if any response to treatment and it tends to result in progressive cognitive dysfunction.
When in doubt about specific products or doses of supplements for pets, please consult with your veterinarian.
Supplements for Cognitive and Brain Health
Medium-Chain Triglycerides – Diets high in medium-chain triglycerides (MCTs), a type of fatty acid, are shown to support brain health and cognitive ability plus help with seizure control. Diets that are known to be high in medium-chain triglycerides include prescription diets such as Hills B/d (Brain Diet) and Purina NeuroCare. There is also an over-the-counter diet called Purina Bright Minds that is supposed to help with canine cognition.
Studies using MCTs are variable and show efficacy in reducing seizure frequency when the MCTs are used to supplement 5.5-9% of the dog’s daily energy requirement. Studies are not available to give exact dosages of MCTs to add to a dog’s normal diet, but MCTs can be purchased over the counter and added to meals. MCTs are not generally very palatable, so you may have to mix the MCTs with chicken broth or another appetizing treat.
Omega-3 Fatty Acids – Studies are variable, but currently available data suggests that high doses of Omega-3 fatty acids can contribute to brain health and cognition. Studies in humans also indicated that B vitamin supplementation only helped patients with high blood concentrations of Omega 3 PUFAs.
The goal dosage for Omega-3 fatty acids is approximately 1000mg per 10 lbs of body weight. When adding omega-3 fatty acids to your pet’s diet, start with low doses and work your way up since diarrhea can be a common side effect. Omega fatty acids should be used with caution in dogs that are prone to frequent pancreatitis or dogs with hemostatic/bleeding disorders.
SAMe (S-adenosylmethionine) – A nutraceutical that is frequently found in liver supplements; however, it is also believed to play important roles in receptor function, neurotransmitter turnover, and the promotion of endogenous antioxidants.
A study in aged Beagles and cats without diagnosed cognitive dysfunction syndrome showed that supplementation with SAMEe improved executive function including goal-oriented behavior, decision-making, and problem-solving. In patients with cognitive dysfunction, SAMe improved activity and awareness and decreased their mental impairment scores. The most common way to supplement SAMe in dogs is with over-the-counter products such as Denamarin or SAMeLQ, dosed at 20mg/kg and rounded to the nearest tablet size.
Probiotics and the Gut-Brain Axis – There are many studies about the gut-brain axis and its effects on brain function and behavior. A healthy microbiome promotes healthy regulation of gastrointestinal peptides, hormones, cytokines, chemokines, activation of the immune system, and bidirectional communication with the brain via the vagus nerve.
In people, there are clear associations between the health of the microbiome and anxiety and depression, and there is growing support for the role of the microbiome and cognitive decline. Common veterinary brand probiotics are all available over-the-counter and include Visbiome, Proviable, and Fortiflora.
When in doubt about specific products or doses, please consult with your veterinarian.
Sage Veterinary Imaging in Sandy, Utah
Find MRI for Dogs in Texas or Utah
Sage Veterinary Imaging has offices in Round Rock, Texas and Sandy, Utah. Dr. Jaime Sage, the founder, received her veterinary training at Texas A&M. After completing a radiology residency, she received further training as an MRI specialist with Patrick Gavin, PhD, DACVR/RO, one of the early pioneers of veterinary MRI.
Dr. Sage is currently president of the CT/MRI society of the American College of Veterinary Radiology and has issued over 20,000 MRI reports over the past 15 years. She lectures frequently at meetings and conferences worldwide.
For more information on where to find an MRI scan for dogs in Texas or Utah, go to our Contact Us page to learn more.
Resources:
Han, F. Y., Conboy-Schmidt, L., Rybachuk, G., Volk, H. A., Zanghi, B., Pan, Y., & Borges, K. (2021, August 1). Dietary medium chain triglycerides for management of epilepsy: New data from human, dog, and rodent studies. Epilepsia. John Wiley and Sons Inc.
May, K. A., & Laflamme, D. P. (2019). Nutrition and the aging brain of dogs and cats. Journal of the American Veterinary Medical Association, 255(11), 1245–1254. Nutrition and the aging brain of dogs and cats
