Health & Wellbeing

Poor sleep may predict Alzheimer’s onset years before symptoms appear

Poor sleep may predict Alzheim...
Research suggests fragmented sleep and low-levels of slow-wave sleep can predict the rate by which toxic Alzheimer's-causing proteins accumulate in one's brain
Research suggests fragmented sleep and low-levels of slow-wave sleep can predict the rate by which toxic Alzheimer's-causing proteins accumulate in one's brain
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Research suggests fragmented sleep and low-levels of slow-wave sleep can predict the rate by which toxic Alzheimer's-causing proteins accumulate in one's brain
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Research suggests fragmented sleep and low-levels of slow-wave sleep can predict the rate by which toxic Alzheimer's-causing proteins accumulate in one's brain

A robust new study from researchers at UC Berkeley has found a consistent association between poor sleep and greater accumulation of the toxic proteins thought to be the pathological cause of Alzheimer’s disease. The researchers suggest fragmented sleep could be an effective early way to predict those most at risk of developing the neurodegenerative disease.

An impressive volume of study over the past few years has homed in on the relationship between sleep and neurodegenerative disease. Irregular and fragmented sleep is a well-known symptom of Alzheimer’s disease and some researchers are beginning to suggest poor sleep may not just be a consequence of the neurodegeneration associated with the disease, but a potential cause as well.

Animal and human studies have effectively demonstrated as little as one night of disrupted sleep can increase accumulations of the toxic proteins associated with Alzheimer’s disease. Researchers have also homed in on the deep slow-wave phase of sleep as a key mechanism our brains utilize to clear our toxic proteins.

“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,” says lead author on the new study, Joseph Winer. “But what hasn’t been tested before is whether your sleep right now predicts what’s going to happen to you years later. And that’s the question we had.”

The researchers recruited 32 cognitively healthy adults in their mid-70s, all who initially participated in an overnight sleep-lab stay allowing the researchers to record baseline sleep behaviors. Over the next few years the subjects periodically completed PET scans tracking the growth of amyloid plaques in their brains.

A clear correlation was identified between the subjects’ baseline sleep quality and accumulation of amyloid plaques over the subsequent few years. In particular, the results suggest fragmented sleep and lower volumes of non-REM slow-wave sleep signaled the greatest increases in amyloid plaque build-up.

“We have found that 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,” says Matthew Walker, senior author on the new study. “Measuring sleep effectively helps us travel into the future and estimate where your amyloid buildup will be.”

It is important to note, the new study only examined cognitively healthy older adults. So while the research does offer evidence disrupted sleep can predict amyloid plaque accumulations in the future, it does not provide evidence these particular aggregations directly lead to the development of Alzheimer’s, or even mild dementia.

The next steps for the research will be to investigate whether interventions to improve sleep quality can directly influence the rate of amyloid plaque accumulation. Longer-term studies will also be necessary to understand whether Alzheimer’s risk can be reduced by improving sleep behavior in middle-aged subjects.

“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,” says Winer. “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.”

The new study was published in the journal Current Biology.

Source: UC Berkeley

6 comments
Eric Townsend
“May” is a dangerous word to bandy about.... nothing like making people worry......
Sheesh.....
James Brett
Perhaps it's the build up of amyloid plaques that's causing poor sleep quality in the first place?
Ana Tamayo
Impaired sleep has been associated with Alzheimer’s disease. Studies suggest that sleep plays a role in clearing beta-amyloid out of the brain. Moreover, lack of sleep has been shown to elevate brain beta-amyloid levels in mice. Less is known about the impact of sleep deprivation on beta-amyloid levels in people.
BlueOak
Yet another “association is causation” leap fallacy in the media.
Jinpa
A "study" of 32 subjects may be correlation, but it is unconvincingly short of causation. The number of other possible correlations probably is immeasurable. How about preference for one rock & roll singer vs another? Or preference for one brand of burger vs another, with or without salt on the fries? A study of 320,000, double blind, maybe, provided it is accompanied by an exhaustive list of other medical conditions, PTSD-like events, foods eaten and avoided, paints and other VOCs from rugs and insulation inhaled, and so on also evaluated.
xs400
Psychiatric drugs cause Alzheimer’s. Plenty of proof.