A lack of sleep promotes Alzheimer's disease
Christiane Fux studied journalism and psychology in Hamburg. The experienced medical editor has been writing magazine articles, news and factual texts on all conceivable health topics since 2001. In addition to her work for, Christiane Fux is also active in prose. Her first crime novel was published in 2012, and she also writes, designs and publishes her own crime plays.
More posts by Christiane Fux All content is checked by medical journalists.Difficulty sleeping can be an early sign of dementia. But now it has been shown that, conversely, a lack of sleep could also favor Alzheimer's: Even after a sleepless night, so-called beta-amyloids accumulate in the brain.
These proteins are metabolic waste products that accumulate in the brain water. In Alzheimer's patients, these proteins clump together and form plaques that could herald the destruction of the nerve cells.
Researchers have already observed in mice that lack of sleep increases Βeta-amyloid levels. In addition, previous research has shown that people who report sleep disorders have more Βeta-amyloid in their brains.
Impact of lack of sleep
A team led by Dr. Ehsan Shoki-Kojori from the National Institute on Alcohol Abuse and Alcoholism (NIAAA) has now for the first time investigated the effects of lack of sleep on the amyloid beta concentration in the human brain. To do this, the researchers scanned the brains of 20 healthy volunteers between the ages of 20 and 72 years after they had worn pajamas for 32 hours.
Using a position emission tomograph (PIT), they determined that the protein waste in the participants' thalamus and hippocampus had accumulated by an average of 5 percent. These brain regions show pathological changes even in the early stages of Alzheimer's disease.
It is true that the Βeta-amyloid exposure increases by around 17 percent even in healthy people from adolescence to old age. In people with Alzheimer's disease, however, it is increased by up to 43 percent compared to healthy people of the same age.
A lack of sleep is not the same for everyone
Interestingly, the lack of sleep did not affect all participants equally: the degree of Βeta-amyloid increase varied considerably, regardless of gender and age. The more Βeta-amyloid accumulated, the more the test subjects' mood deteriorated after sleep deprivation.
Nocturnal garbage collection in the brain
During sleep, therefore, important clean-up tasks seem to be going on in the brain that eliminate beta-amyloids. The so-called glymphatic system, which is responsible for the disposal of waste materials in the central nervous system, plays a decisive role.
In fact, previous research has shown that eta-amyloid levels in the brain are highest before sleep and lowest after waking up. While the consequences of a sleepless night should be gradually compensated for by the body's own garbage disposal, a chronic lack of sleep could cause Βeta-amyloid to accumulate in the brain.
Can sleep hygiene prevent Alzheimer's?
"We have clear indications that sleep disorders could contribute to Alzheimer's," says Shoki-Kojori. The results indicated how important good sleep hygiene is for proper brain function and that it could possibly even prevent Alzheimer's. Further studies with more participants would have to confirm the result.
