Problems with shuteye can signal the disease years before the memory symptoms appear.
In the study, researchers recruited 101 people with healthy memories and thinking skills, but who were considered at higher risk of Alzheimer’s—either due to a family history, or because they carried a gene that raised their risk for it. Then, they surveyed them about their sleep quality, and took samples of their spinal fluid to test for markers of Alzheimer’s.
The findings? People who reported poorer sleep quality, more problems sleeping, and more sleepiness during the day showed more markers of Alzheimer’s in their spinal fluid than those who slept better. These markers included amyloid and tau—proteins that cause the plaques and tangles, respectively, that are seen in brains of Alzheimer’s patients—as well as cell damage and inflammation.
It’s possible that lack of sleep, or disrupted sleep, messes with your brain’s clearance system that would otherwise remove the proteins before they have a chance to build up, study author Barbara B. Bendlin, Ph.D., explained in a statement.
Now, not everyone who reported problems sleeping showed abnormalities in their spinal fluid, she says. And it’s also not clear if the sleep issues are causing the development of the disease, or if the latent disease affects the quality of sleep.
Still, the findings suggest that sleep may be a modifiable risk factor of Alzheimer’s—and since there are already many effective ways to improve sleep, it’s possible that doing so for people at risk of Alzheimer’s may prevent the disease or delay its onset.