Visiting Vet: Does your elder pup have CDS?

Watch out for certain age-related symptoms, and ask your vet.

0
Flower before she passed away in 2017. — Michelle Gerhard Jasny V.M.D.

I still think about the first time I just could not remember something I knew I should know. I was trying to recall the name of a very famous actress. Someone whose name I had known for half a century. But I just couldn’t retrieve it. It was frightening, like searching in the dark, blindfolded, for something I had lost. Many of us develop some degree of memory loss and cognitive decline as we age. We forget for a moment whether to turn right or left at a familiar intersection, or how to spell a common word. We may worry it is something more than “normal” aging. Do we have early Alzheimer’s? Dementia? A brian tumor? Or are we just, well, getting old?

In senior dogs and cats this kind of gradual decline is called cognitive dysfunction syndrome (CDS). We can’t ask Gramps the Gordon setter what year it is, or to name the president. Instead we look for signs of altered behavior. I have a CDS checklist for dogs. Does Gramps wander aimlessly, or appear lost or confused in the house or yard? Does he get “stuck” in corners or behind furniture? Does he stare into space or at the walls? Some of these behaviors may simply be explained by what we call sensory deprivation, i.e. loss of vision, hearing, and/or sense of smell. When Gramps doesn’t respond when you call him, maybe he just doesn’t hear you … but maybe he has CDS, and no longer recognizes his name. My checklist continues with questions that can be difficult for owners to assess. Sometimes the onset of CDS is so gradual people fail to recognize it. When Gramps no longer greets you at the door when you get home, you may assume he has arthritis and doesn’t feel like getting up … but maybe he has CDS and actually doesn’t remember who you are or where he is. 

Phone calls to the veterinarian usually begin when Gramps starts having serious trouble with “tasks of daily living.” Housebreaking. Sleep cycles. He may sleep all day, then keep you up all night pacing. He may urinate or defecate in the living room, despite having been perfectly housebroken since he was a puppy. He may forget to ask to go out, or go to the wrong door, or go outside, but then look like he forgot why he is there. I know that feeling. Why did I go into the kitchen? I forget.

The causes of CDS are complex. We know as animals age, their brains gradually decrease in weight and size. The number of neurons decreases, and there are changes in neurotransmitter activity. A neurotoxin protein called beta amyloid accumulates in certain portions of the brain, which is often seen in the brain of people with Alzheimer’s, and is thought to contribute to CDS in pets. There may be damage to the brain’s blood supply, with lesions such as microhemorrhages and infarcts. I’ll leave the more detailed explanations to the neurologist, and leave it at that. Suffice it to say, a CDS diagnosis is generally made by getting a careful history and trying to rule out other maladies that may cause behavioral changes, such as brain tumors, infections, or metabolic and endocrine disorders. For those who want, your veterinarian can refer you to a neurologist for advanced diagnostics and imaging, but few owners typically pursue this, considering Gramps’ age.

So what can we do for elderly CDS dogs? There is no known cure, but there are drugs and supplements that might improve cognitive function or slow the progression. Selegiline (Anipryl) is the only medication approved by the FDA to treat CDS in dogs in the U.S. It is an MAO inhibitor (a type of antidepressant) that, given in the morning, may help improve daytime alertness, activity, and housebreaking. Selegiline can take weeks to take effect, has a fairly high incidence of side effects, and cannot be combined with a number of other drugs, so if you are interested in trying it, work closely with your veterinarian. 

Other prescription medications, including antianxiety drugs, antidepressants, and/or mild sedatives, may be helpful, as CDS, and the accompanying disorientation, often results in anxiety, fear, and agitation, particularly at night or when left alone. Try using an OTC calming pheromone product like Adaptil, available in diffusers or collar form. Commercial dog foods aimed at brain health, such as Hills Brain Aging Care (B/D) and Purina Pro Plan Veterinary Diets NeuroCare, contain supplements like antioxidants, mitochondrial cofactors, medium chain triglycerides, and/or omega-3 fatty acids touted to support memory and learning ability. Other OTC supplements such as s-adenylyl-l-methionine (SAMe), melatonin, and ginkgo biloba may be helpful in various ways, but always check with your veterinarian first. 

It’s hard on owners when Gramps barks or paces constantly, and just can’t settle down, especially when the family is trying to sleep. Don’t punish him, no matter how frustrating things get. That will just make things worse. Environmental supports are crucial. Keep things routine and familiar, to minimize confusion. Don’t move the furniture. Keep a predictable schedule. Regular walks for exercise, scheduled play time, toys for mental stimulation. The more you keep Gramps physically and mentally active, the better to help keep his mind as alert and functional as possible. Have a night-night routine. Take him out to eliminate right before bedtime. Go with him. Consider getting him an extra comfy orthopedic bed, maybe one with a dog-safe warming system. 

Don’t assume it’s “just” old age if your dog is showing progressive confusion, reversal of day-night sleep patterns, loss of housebreaking, or other symptoms consistent with CDS. Talk to your veterinarian. Together we can evaluate and treat contributing factors such as pain, sensory deprivation, anxiety, and other illnesses. Then, by process of trial and error, we can find the right combination of medications, activities, and environmental modification for his specific needs. I’m going to go finish the crossword puzzle now. The actress? Elizabeth Taylor.