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If forgetting things has become a normal thing for you then it can be a sign of the onset of Alzheimer’s disease. And who’s to blame? Poor sleep. In today’s world of hustle and meeting deadlines, our sleep pattern is really messed up and this lockdown has been the cherry in the top.
A recent research published in the journal Current Biology found that based on your sleep patterns neuroscientists can now estimate a time frame for when Alzheimer’s is most likely to strike in a person’s lifetime. Their findings suggest that one defence against this virulent form of dementia (for which no treatment currently exists) is deep, restorative sleep, and plenty of it.
University of California Berkeley professor of psychology and neuroscience and senior author of the paper, Matthew Walker says: “The sleep you’re having right now is almost like a crystal ball telling you when and how fast Alzheimer’s pathology will develop in your brain. The silver lining here is that there’s something we can do about it. The brainwashes itself during deep sleep, and so there may be a chance to turn back the clock by getting more sleep earlier in life.”
The researchers studied the sleep quality of the study participants
The researchers matched the overnight sleep quality of 32 healthy older adults against the buildup in their brains of the toxic plaque known as beta-amyloid—a key player in the onset and progression of Alzheimer’s. This afflicts more than 40 million people worldwide by destroying their memory pathways and other brain functions.
For the experiment, each participant spent an eight-hour night of sleep in Walker’s lab while undergoing polysomnography, a battery of tests that record brain waves, heart rate, blood-oxygen levels and other physiological measures of sleep quality.
Over the course of the multi-year study, the researchers periodically tracked the growth rate of the beta-amyloid protein in the participants’ brains using positron emission tomography, or PET scans and compared the individuals’ beta-amyloid levels to their sleep profiles.
They found that…
The study participants who started out experiencing more fragmented sleep and less non-rapid eye movement (non-REM) slow-wave sleep were most likely to show an increase in beta-amyloid over the course of the study.
Although all participants remained healthy throughout the study period, the trajectory of their beta-amyloid growth correlated with baseline sleep quality. The researchers were able to forecast the increase in beta-amyloid plaques, which are thought to mark the beginning of Alzheimer’s.
Joseph Winer the lead author and a PhD student in Walker’s Center for Human Sleep Science at UC Berkeley says:
“Rather than waiting for someone to develop dementia many years down the road, we are able to assess how sleep quality predicts changes in beta-amyloid plaques. In doing so, we can measure how quickly this toxic protein accumulates in the brain over time, which can indicate the beginning of Alzheimer’s disease.”
What is the link between poor sleep and Alzheimer’s disease?
While previous studies have found that sleep cleanses the brain of beta-amyloid deposits, the new results reinforce the link between poor sleep and the disease by identifying deep non-REM slow-wave sleep as the target of intervention against cognitive decline.
The researchers pointed out that though genetic testing can predict one’s inherent susceptibility to Alzheimer’s, and blood tests offer a diagnostic tool, neither offers the potential for a lifestyle therapeutic intervention that sleep does.
“If deep, restorative sleep can slow down this disease, we should be making it a major priority. And if physicians know about this connection, they can ask their older patients about their sleep quality and suggest sleep as a prevention strategy,” says Winer.
The researchers focused on brain activity present during deep slow-wave sleep. They also assessed the study participants’ sleep efficiency, which is defined as actual time spent asleep, as opposed to lying sleepless in bed. The results supported their hypothesis that sleep quality is a biomarker and predictor of the disease down the road.
“We know there’s a connection between people’s sleep quality and what’s going on in the brain, in terms of Alzheimer’s disease. But what hasn’t been tested before is whether your sleep right now predicts what’s going to happen to you years later,” Winer said. “And that’s the question we had.”
And they got their answer: “Measuring sleep effectively helps us travel into the future and estimate where your amyloid buildup will be,” Walker added
“Our hope is that if we intervene, then in three or four years the buildup is no longer where we thought it would be because we improved their sleep. Indeed, if we can bend the arrow of Alzheimer’s risk downward by improving sleep, it would be a significant and hopeful advance,” he concluded.