Sometimes referred to as ‘doggy dementia’ Canine Cognitive Dysfunction Syndrome affects as many as one in four older dogs. Dr. Charlotte Gray, one of the UK’s best known and most respected vets, explains how a simple change of diet can help to alleviate the symptoms and improve the condition.
When dogs get older, we often notice that they go a little grey around the muzzle. We might notice they sleep more, too, and slow down on walks. We might even notice some stiffness or arthritis. How many of us notice, however, brain ageing?
When surveyed, over a quarter (28%) of eleven to twelve-year-old-dogs were reported to be showing at least one sign of Canine Cognitive Dysfunction Syndrome (CDS) by their owners. In general practice, though, we frequently aren’t aware of these signs until a dog becomes confused and anxious.
There are lots of simple actions we can take to slow the progression of this common condition and this article will discuss some of the things you can do if your pet is affected.
What is Canine Cognitive Dysfunction Syndrome (CDS)?
CDS is sometimes described as ‘doggy dementia’. Indeed, the brain changes seen in CDS share many similarities with Alzheimer’s disease in humans, including a loss of nerve tissue (neurons) and an increase in abnormal deposits (called amyloid) in the blood vessels of the brain. Symptoms of CDS can include confusion, increased anxiety and loss of normal night-day cycles. Some dogs will forget previously learned behaviours like toilet training and may pace and bark more than they used to.
How do we diagnose CDS?
CDS generally affects dogs in their later years (10+) with two-thirds of dogs over 15 showing symptoms. It is a diagnosis that is based on behavioural signs, but since other (medical) conditions can look very similar, it’s important to rule out other diseases first. For example, pain from arthritis is also a common cause of anxiety, pacing, and inability to settle down at night. Conditions affecting the liver can also make a diagnosis more difficult.
Once your vet has ruled out these other conditions (including pain and liver or kidney dysfunction), CDS may be diagnosed based on having one or more of these signs:
- Confusion and loss of spatial orientation. Dogs may get lost in familiar locations, go to the wrong (hinge) side of a door, may get stuck and find it difficult to navigate around obstacles or fail to recognise familiar people, pets or places.
- Relationships and social behaviour. Dogs may become over-dependent and clingy. The may have decreased greeting behaviours.
- Activity. Dogs may display increased, decreased or repetitive behaviours. Some dogs may stare, wander, or lick household objects or owners.
- Agitation or anxiety. Dogs may bark or whine more or may be more irritable or aggressive, and some may develop new phobias.
- Food. Some dogs will develop increased or decreased appetite. It’s important that medical causes of these two symptoms are ruled out before these are assumed to be due to CDS, but pets with CDS can also display unusual behaviour around eating – even if they are well.
- Decreased responsiveness to stimuli. Some dogs with CDS will have a decline in vision, hearing or sense of smell due to brain changes (of course – changes to eyes and ears may also contribute to these changes).
- Decreased self-care. Dogs and cats may clean themselves less – again – it’s important to rule out pain here.
- Restless sleep or awake at night.
- Learning and memory. Previously house-trained dogs may toilet in the house even if they have been out recently. Dogs may even forget previously learned commands or display ‘naughty’ behaviours similar to when they were puppies.
What can we do about Cognitive Dysfunction?
There are a few things we can do to improve brain function in dogs.
Medications
There are medications designed to improve cognitive function in
elderly dogs. Some act on chemicals in the brain to improve the signals transmission, whilst others will improve blood flow in the brain. Your vet will help you to decide whether these medications are likely to be needed for your dog.
Food!
Modification of food can be vastly helpful in slowing progression and supporting brain function in dogs with cognitive dysfunction. Much of the ageing process all over the body is caused by little damaging particles called ‘free radicals’. Free radicals are produced by normal internal chemical reactions in the body as well as inflammatory processes. It is the job of ‘antioxidants’ to mop up these free radicals and prevent them from damaging neighbouring cells.
In a study of a hundred and twenty-five ageing beagles showing signs of cognitive dysfunction, supplying a diet enriched with antioxidants resulted in significant improvement in disorientation, sleep patterns and house soiling after 30 days. After 60 days, activity levels had also improved. The dogs had also improved awareness of their surroundings and families, and showed increased enthusiasm greeting owners.
Where can we get antioxidants from?
Don’t be fooled into thinking you always need to buy capsules and powders to supply antioxidants. Antioxidants are in all sorts of normal foods. The human five-a-day recommendation is not just an attempt to provide essential nutrients, but also to provide plenty of varied antioxidants for general health.
Some common nutrients that most of us have heard of (like Vitamin C, E and Selenium) are antioxidants. They play important roles in mopping up these free radicals and can be obtained from food. Vitamin C is common in fruit and vegetables, and selenium is present in high levels in both brazil nuts and kidney (not too much please!).
Vitamin E is found in wheatgerm oil, although when looking to provide Vitamin E at high levels (especially if your dog is unable to tolerate a higher fat diet) sometimes supplementation is handy. Vitamin E liquid is available as part of some veterinary formulated supplements for cognitive dysfunction and is also widely available as a human supplement. Vitamin E supplements are generally very safe so long as you make sure any human Vitamin E supplement contains no additional ingredients that might harm your dog (like sweeteners or added vitamins – especially Vitamin D).
There are lots of other antioxidants too. Resveratrol from fruits like blueberries can protect the brain in Alzheimers patients, and Flavonoids like Quercetin from kale and apples can protect the lining of blood vessels in the brain.
Whilst there are rafts of evidence for individual antioxidants, you actually don’t have to use measured doses of specific ingredients to make a difference.
Existing guidance for fruit and vegetables in CDS suggests that we use a good variety of fruit and vegetables of various types and colours, and that you should aim for at least 5% of the diet to be made up of them.
As dogs are not great chewers, it is also likely to be helpful to blend vegetables and fruit (unless they are just for fun) to improve digestion and absorption of the vitamins, minerals and antioxidants.
Other nutrients
Some aspects of cognitive ageing are to do with poor energy production in the brain. Just like muscles, the brain needs to convert food (in particular glucose) into energy. Mitochondria are the little engines responsible for doing this.
With age, mitochondria (like old engines) become less effective/less functional, making it more challenging to produce enough energy for the brain cells. This in turn can start to affect brain function and behaviour contributing to the ‘senile’ signs that we recognise.
There are some nutrients we can use to specifically help to support these little mitochondrial engines to help keep them in good working order right into old age.
Alpha lipoic acid and L-carnitine both support mitochondria, and both are found in red meat/organs. Alpha lipoic acid is also found in potato, broccoli, L-carnitine is also found in dairy products.
By supporting the mitochondria they may be able to produce more energy for the brain improving cognition.
These two nutrients are often found in supplements formulated for dogs with cognitive dysfunction. For pets that eat lower meat diets, or just those who need a boost, using a supplemental form of these two might be useful.
Omega 3 Fatty Acids
Omega 3 fatty acids (in particular EPA and DHA) have broad beneficial effects in older dogs including supporting conditions like arthritis. DHA is involved in the brain in particular and supplying good levels improves learning and memory in humans and animals of different ages.
Omega 3 can be obtained from fish or fish oil, but for pets with diseases requiring higher levels it can be useful to use distilled (concentrated) versions.
Fish oil is a great source of EPA and DHA but it also contains a lot of vitamins A and D alongside a lot of calories. Whilst these aren’t harmful in normal amounts, eating too much of these vitamins can be dangerous. Using a distilled oil means that you can use much less of it and without the risk of excessive vitamin A, D or adding tremendous amounts of calories to older dogs who often already have reduced calorie needs. There are a few veterinary products and a few human ones that can provide this – but take extra care with human versions of this particular one – – many contain dangerous levels of vitamin D so read the labels carefully and consult with a vet or nutritionist if you aren’t sure.
Medium Chain Triglycerides (MCT) – Coconut oil
The brain is heavily reliant on glucose supply to function. It is not as good at using other fuels (like fat) as the rest of the body. As we just learned, the ability of the brain to process glucose into brain-energy declines with age. MCT oils may provide a solution to this.
MCTs are special types of fatty acids that are found in high levels in coconut oil. They are unique compared to other fats. Whilst the brain cannot usually use other fats and protein efficiently as fuel, it CAN use the chemicals produced by breakdown of MCTs.
Ketones
Ketones provide an alternative energy source for the brain cells helping to make up for the reduced ability to make energy from glucose that occurs with age. In a study of 100 dogs, those eating a diet with 6.5% MCT oil showed significant improvement in 6 measured markers of CDS within 30 days.
Supplementing with coconut oil is safe for most pets – but introduce it slowly – a sudden change of fat level can upset tummies. For a small dog, a teaspoon per day is a reasonable aim. For a big dog (labrador) 1-2 tablespoons. Start with a little and work up. Don’t forget – oils and fats are calories! It’s important older dogs do not become overweight so you might need to adjust their food a little to compensate for these.
Summary
Canine cognitive dysfunction (CDS) is more common than we realise and is often overlooked for many years before treatment is sought.
Since some of the signs of CDS may also look a bit like other medical conditions it is important to get a check-up with the vet to rule these out first.
Once a diagnosis of CDS has been made there are lots of simple things you can do to help improve your elderly dogs brain function.
Fruit, vegetables, omega 3 and coconut oil are all simple additions. Providing a diet with plenty of red meat (or for those eating dry foods – adding a little red meat as a topper) might help to provide additional L-carnitine and alpha-lipoic acid to help support the mitochondrial ‘engines’ that are responsible for powering ageing brain cells.
In severe cases, your vet may also be able to provide medication to help too.
In any case, research shows that signs of CDS can be significantly improved with these simple dietary changes so as always – never underestimate the power of nutrition!
References:
- Small Animal Clinical Nutrition 5th Edition
- Use of medium chain triglyceride (MCT) oil in subjects with Alzheimer’s disease: A randomized, double-blind, placebo-controlled, crossover study, with an open-label extension.Angela G. Juby et al – Published online 2022 Mar 14 Alzheimers Dement (N Y). 2022; 8(1): e12259.
- Efficacy of a Therapeutic Diet on Dogs With Signs of Cognitive Dysfunction Syndrome (CDS): A Prospective Double Blinded Placebo Controlled Clinical Study. Yuanlong Pan et al,Front Nutr. 2018; 5: 127. Published online 2018 Dec 12. doi: 10.3389/fnut.2018.00127
Article by Dr Charlotte Gray MA (hons) Vet MB MRCVS . Dr Charlotte Gray is a vet who specialises in canine and feline nutrition. She qualified from Cambridge University, where she also did a Masters Degree in Zoology (honours). Dr Gray has helped us with our formulations and you can learn more about her here: www.companion-nutrition.co.uk
