“Dogs with Dementia Experience Similar Sleep Problems as Humans with Alzheimer’s Disease: Study”

And that is striking, because exactly the same is the case with humans.

Alzheimer’s disease is known to disrupt normal sleep patterns. People not only have trouble falling asleep, but also having trouble sleeping through the night. Our loyal four-legged friends suffer from something similar, as shown a new study On. Because dogs with dementia are also regularly plagued by a bad night’s sleep.

Study
In the study, the researchers collected 28 elderly dogs (17 females and 11 males). The dogs underwent a full physical examination and additionally completed cognitive tests. Their owners also had the Canine Dementia Scale (CADES) questionnaire to determine the severity of their cognitive decline. Then the sleep study began.

Sleep study
The dogs did two sleep sessions in the lab. The first session was designed to get the dogs used to the new environment and the electrodes taped to them. During the second session, brain activity was measured during a short two-hour nap. The researchers, unlike previous sleep studies in dogs, used non-invasive techniques to collect data. For example, the dogs were not anesthetized and the electrodes were attached to their heads with a sticky gel.

NREM a REM
To measure the electrical activity of the brain, the researchers used EEG (electroencephalography). EEG measures four stages of sleep: alertness, drowsiness, NREM, and REM. NREM (or Non-REM sleep) is a deep state of sleep prior to REM. Dreams are virtually non-existent during NREM and, unlike REM sleep, the muscles are not paralyzed. “During NREM, the brain clears toxins,” says researcher Alejandra Mondino. “Beta-amyloid proteins involved in Alzheimer’s disease are also broken down.” REM (short for rapid eye movement) is the stage of sleep where vivid dreams are experienced. “This sleep phase is very important for memory,” says Mondino. For example, scientists suspect that this sleep phase plays a role in processes that ensure that memories remain stored in our memory.

Did you know…
…the length of REM sleep does not stay the same? REM sleep decreases as we get older. Newborns spend about 50 percent of their sleep in REM sleep. By the age of ten this has dropped to 25 percent and adults spend only 15 percent of their time in REM sleep. The significant decline in REM sleep occurs around the second year of life.

The researchers studied the time the dogs spent in each state of sleep. They then correlated this with the results of their cognitive tests and the CADES questionnaire.

Sleep disorders
An interesting conclusion emerges from the study. Because the more demented the dog, the less time he or she appears to spend in NREM and REM sleep. In addition, the researchers found that dogs with more advanced dementia often suffered from sleep disturbances and generally slept less than dogs without cognitive problems.

Brain doesn’t participate
It means that dementia and poor sleep also go hand in hand in dogs. “In addition to a shorter sleep time, we also saw on the EEG scans that their brain remains alert,” explains Mondino. “In other words, if they manage to sleep, their brain won’t participate.” So their brains remain active to a certain extent. So even though the dogs are trying to rest, the brain is probably not really sleeping.

Agreement
It means dogs with dementia bear striking similarities to people with Alzheimer’s disease. Because apparently dogs are also plagued by a bad night’s sleep and light, interrupted sleep in old age. In short, dogs with dementia suffer from the same sleep disorders as people with dementia.

Vicious circle
Scientists have long suspected that the link between sleep disorders and Alzheimer’s is actually a vicious circle. Alzheimer’s disease causes changes in the brain that disrupt sleep. But poor sleep, in turn, accelerates harmful changes in the brain. For example, people who sleep poorly are known to have higher levels of both amyloid and tau (important Alzheimer’s proteins) in the brain.

The fact that it has now also been established that dogs suffering from dementia suffer from sleep problems is an important discovery. On the one hand, because this makes it easier to reveal cognitive decline in dogs. For example, the study may lead to earlier diagnosis and treatment in older dogs showing signs of dementia. “In addition, the study suggests that dogs may be a good model for Alzheimer’s disease research,” notes study researcher Natasha Olby. “Hopefully, further studies on dogs will help develop better treatments for humans.”