Sleep Disruptions Could Be First Sign of Alzheimer's
If you are someone who has trouble falling asleep at night, or who has a lot of sleep disruptions, you might want to take it seriously, as a new study claims that sleep disruptions may be early signs of Alzheimer's disease.
According to scientists at Washington University School of Medicine in St. Louis who conducted their experiment on mice, the earliest signs of Alzheimer's plaques appear in the brain and significantly disrupt the normal sleep-wake cycle.
"If sleep abnormalities begin this early in the course of human Alzheimer's disease, those changes could provide us with an easily detectable sign of pathology," senior author David M. Holtzman, MD, the Andrew B. and Gretchen P. Jones Professor and head of Washington University's Department of Neurology was quoted as saying by Medical Xpress.
"As we start to treat Alzheimer's patients before the onset of dementia, the presence or absence of sleep problems may be a rapid indicator of whether the new treatments are succeeding."
In an earlier study published by Holtzman in 2009, he has shown that primary ingredient of the plaques in the brain, naturally rise when healthy young mice are awake and drop after they go to sleep.
Development of brain plaques increased when the mice was deprived of sleep.
Also, a protein called amyloid beta, a similar rising and falling of the plaque component detected in the cerebrospinal fluid of healthy humans studied by co-author Randall Bateman, MD, the Charles F. and Joanne Knight Distinguished Professor of Neurology at Washington University, Medical Xpress reported.
The current study shows that in both mice and humans, when the earliest indicators of brain plaques appear, the natural fluctuations in amyloid beta levels stop.
"We suspect that the plaques are pulling in amyloid beta, removing it from the processes that would normally clear it from the brain," Holtzman says.
In order to confirm the correlation between amyloid beta and sleep disruption, the researchers administered a jab against amyloid beta to a new group of mice with the same genetic modifications.
It was found that in this new group of mice, there was no brain plaque development as with advancing age. While their sleeping patterns remained normal, the levels of amyloid beta levels in the brain also continued to rise and fall regularly.
"If these sleep problems exist, we don't yet know exactly what form they take-reduced sleep overall or trouble staying asleep or something else entirely," Holtzman says. "But we're working to find out."
The report appeared on Sept. 5 in Science Translational Medicine