Cognitive dysfunction syndrome
Overview
- varies between 14% and 35% of the pet dog population
- in dogs 11-12 years old 28%
- in dogs 15-16 years old 68%
Cause
- Oxidative and inflammatory neuronal damage
- Excitotoxic neuronal damage
- Brain vascular compromise
- Neuronal mitochondrial dysfunction
- Deposition of toxic beta amyloid (Aβ) and tau protein around neurons and blood vessels
- Premature neuronal death (apoptosis)
- Decline of brain cholinergic activity
- Impaired neurogenesis
Cognitive dysfunction syndrome (CDS) is a common age-related disease in dogs that affects the brain, causing deterioration similar to Alzheimer's disease in humans.
Dogs may start to develop CDS around nine years of age, or older. The condition may be underdiagnosed since the behavioral changes progress slowly, and owners may assume that some changes are a normal part of aging.
Early intervention with environmental enrichment, diet and medical management can improve the quality of life for dogs affected by CDS.
One of the degenerative changes that occurs is the build-up of a protein called beta-amyloid, which creates toxic conditions for neurons. As the neurons stop functioning properly or die off, the brain loses its capacity for processing information, and this breakdown of internal communication leads to the physical and behavioral changes that owners observe.
Clinical sign
CDS may start as one clinical sign and progress over time, or have several apparent signs. The most common may include:
- Disorientation — Getting lost in familiar places, stuck in corners, staring into space
- Interaction changes — Suddenly clingy or avoidant, not recognizing familiar people
- Sleep pattern changes — Wandering the house at night, sleeping more during the day
- House-soiling — Urinating or defecating indoors when they were previously house-trained
- Activity level changes — Decreased interest in playing or doing other activities, restlessness, pacing
- Anxiety — Increased anxiety, new phobias, irritability, aggression
- Learning changes — No longer responding to previously known commands or struggling to learn new ones
Diagnosis
CDS is diagnosed based on the demonstration of clinical signs.
Your veterinarian will perform a thorough physical exam and recommend checking blood and urine tests to rule out other conditions with similar signs, such as pain, arthritis, seizure disorders, systemic illnesses, and vision or hearing loss. In some cases, MRIs can provide advanced imaging to rule out brain tumors or other conditions.
Treatment
Treatment may include a combination of the following: