Study: Older dogs who sleep poorly may have dementia CNN.com

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In a North Carolina veterinary lab, Woofus, a 15-year-old hound mix, lets researchers attach electroencephalography, or EEG, electrodes to his head before stuffing him into a dark, cozy room for an afternoon nap.

While he is napping, the study team will analyze Foss’s brain waves to judge the quality of his sleep. Woofus suffers from Canine Cognitive Dysfunction Syndrome, or CCDS, a canine disorder that is similar to Alzheimer’s disease in humans. Elderly dog ​​owners say he struggles to get enough rest at night.

“Just like humans with Alzheimer’s disease, dogs with Alzheimer’s disease experience sleep disturbances, such as insomnia and sleep fragmentation,” said veterinarian Dr. Natasha Olby, professor of neurology, neurosurgery and gerontology at North Carolina State Veterinary College in Raleigh.

Woofus isn’t the only sleep-deprived dog in this study. On other days in the clinic, Jake, a 13-year-old pointer, and Coco, a 12-year-old dachshund, among others, might be taking naps while researchers look inside their brains.

“Owners of dogs with CCDS have reported that their dogs have difficulty sleeping at night, increased daytime sleepiness or both, as well as rapid vocalizations and vocalizations at night,” Olby said. “This can be very difficult for dog owners—not only are they worried about their pet, but their sleep is also greatly disrupted.”

To see if sleep problems in dogs signal early signs of dementia as they do in people, Olby and her team turned to a group of senior dogs enrolled in an ongoing study to test anti-aging supplements. Twice a year, she said, the dogs visit and “do all sorts of really fun cognitive tests.” “They really enjoy it and love the therapists they work with.”

To be considered for an anti-aging study, a dog must have lived to more than 75% of the life expectancy for his breed or breed mix. A dog also cannot be crippled by arthritis or go blind, because the pet needs to be able to perform tasks designed to test its cognitive abilities.

A dog might, for example, be asked to find a treat hidden under a cup or a snack inside a cylinder that had been sealed at one end by a researcher. By repeating the tasks in the clinic every six months, any decrease in the dog’s mental speed or performance can be tracked.

For the new study that measures a dog’s brain waves during sleep, the researchers used a form of EEG called polysomnography, which is used in sleep clinics to diagnose sleep problems in people.

“It’s the gold standard way of looking at what the brain is doing while we sleep,” Olby said, adding that this is the first dog study to apply the same technique used in humans.

“We stick these electrodes on with a really cool water-soluble conductive glue. And then we wash them off afterwards,” she said. “We don’t use anywhere near as many electrodes as you see on people in the sleep lab, because dogs have a crust and surface area Much less to cover.”

She said she feels really comfortable with the staff, and it wasn’t too difficult to train her 28 large dogs to wear electrodes and walk around with dangling wires without complaint.

To make dogs more comfortable while they nap, owners bring their dogs’ beds from home, which are placed in a white noise-sheltered room.

“The staff sits with them while they nap to make sure they don’t try to pull or eat the electrodes or do anything that might hurt them,” Olby said.

When the brain waves during sleep were compared to a dog’s cognitive test, the researchers found that dogs with severe dementia spent less time in deep sleep and REM sleep, just as people do. The study was recently published in the journal Frontiers in Veterinary Science.

“The dogs that performed worse on memory tests had levels of REM sleep that were not as deep as they should be,” Olby said. “We found the same thing when it came to deep sleep.”

While no one knows the exact mechanism at work — either in humans or in dogs — research like this study It may help scientists better understand the process and find ways to manipulate it, Olby says.

“There is a possibility that we might be able to identify an early signature of change on an EEG that could tell us, ‘Hey, things are starting to slip.'” Because with a chronic neurodegenerative process, we would of course like to be able to intervene sooner rather than later.”

In the meantime, there are medications for anxiety and melatonin for sleep that vets can prescribe as your dog gets older, Olby says. And, as with people, diet and exercise seem to be important factors.

“There have been some really nice studies that show that diets rich in flavonoids, antioxidants, and medium-chain fatty acids can slow the progression of dementia in dogs,” she said. “It’s just like people — if you can eat a Mediterranean diet and do your exercise, you’ll do better.”

Dog dementia is a troubling reality for many senior dogs. Research has found that by the age of 11 or 12, 28% of dogs had mild mild and 10% had severe cognitive impairment. By the time the dogs reached the age of 15, the risk had risen to 68% for cognitive impairment and 35% for severe cognitive impairment. Olby said a 2022 study found that the odds of cognitive impairment in dogs increased by 52% with each year of age.

Pet owners can look for signs of declining mental functioning in their dogs. According to Olby, vets use an acronym called DISHA-AL, which stands for disorientation, reaction changes, sleep/wake cycle alterations, and house soiling; activity changes (increase or decrease); And anxiety, learning and memory.

“One of the first signs is that you will start to see a little bit of confusion as you do with people, they suddenly start making some mistakes and things that you wouldn’t expect them to do,” Olby said.

She added that dogs may also lose learned behaviors, or forget to house train them and start having unintentional accidents around the house.

“There is the classic problem of wandering around and getting lost under the table or something — they can’t process information and know where they are. Changes in the sleep cycle, increased anxiety, all of those things are classic signs of dementia.

Do not assume that this is what is wrong with your dog. Just as with people, other health issues such as metabolic diseases, urinary tract infections, or even brain tumors can mimic the classic signs of dementia.

“High blood pressure can make dogs anxious, for example, so your vet needs to thoroughly examine the dog to rule out disease,” Olby said.