While we’re all separated by extraordinary and countless differences, there is one thing that rings true for the majority of us: we don’t get enough sleep. Or we at least undercut its importance. According to the National Sleep Foundation, young to middle-aged adults should get 7-9 hours of sleep a night, while a healthy range for older adults is 7-8 hours of sleep a night. Most are aware of this recommendation, but they still don’t concede to the professional advice—why? Simply put, our priorities are askew.
Insufficient sleep can have a multitude of harmful effects on our health: it can lead to fatigue, hinder productivity, and even increase our risk of developing serious conditions like heart disease, diabetes, and—according to a new study—Alzheimer’s disease. This study “Effect of sleep on overnight CSF amyloid-beta kinetics” from Washington University School of Medicine in St. Louis says that sleep disruption can cause levels of amyloid beta to rise quicker than the brain’s waste-removal system can dispose of it. These heightened levels of protein can then set off sequence changes in the brain that result in dementia.
Amyloid beta is produced by normal brain activity, but a sleeping brain produces much less. Therefore, staying awake throughout the night when one should be asleep can cause amyloid beta levels in one’s brain to become abnormally high and start combining to form plaques. These plaques damage neurons, which can result in harmful brain changes such as the development of Alzheimer’s.
Senior author and professor of Neurology Randall Bateman explained the significance of his team’s findings: “This study is the clearest demonstration in humans that sleep disruption leads to an increased risk of Alzheimer’s disease through an amyloid beta mechanism. The study showed that it was due to overproduction of amyloid beta during sleep deprivation.”
To reach these findings, Bateman’s team analyzed eight people who were between the ages of 30 and 60 and with no sleep or cognitive concerns. These subjects were randomly assigned to one of three groups: the first group was to get a normal night’s sleep without help from sleep aids; the second was tasked with staying up all night; and the third was to sleep after taking the prescription sleep medication sodium oxybate, which increases deep sleep.
Each aforementioned scenario was monitored for 36 hours, starting in the morning and ending later the following day. In order to monitor changing amyloid beta levels, the researchers took samples of fluid surrounding the brain and spinal cord every two hours from each participant. Then 4-6 months later, the subjects returned to complete at lease one more of the three assignments—four subjects went on to complete all three.
At the end of the experiment, the researchers found that amyloid beta levels in the sleep-deprived participants were 25-30% higher than in those who slept all through the night. Additionally, amyloid beta levels after a sleepless night were similar to those measured in individuals genetically predisposed to develop Alzheimer’s at an abnormally young age. This suggests that consistent and severe sleep problems can lead to cognitive decline.
“I don’t want anyone to think they are going to get Alzheimer’s disease because they pulled an all-nighter in college. One night probably has no effect on your overall risk of Alzheimer’s. We are really much more concerned about people with chronic sleep problems,” explained first author and assistant professor neurology Brendan Lucey, MD. He goes on to say that this study, “could help us figure out how to reduce amyloid beta deposition over time in people whose sleep is chronically disrupted.”
WUSTL (2017, December 28). Lack of Sleep Boosts Levels of Alzheimer’s Protein. NeuroscienceNews. Retrieved December 28, 2017 from http://neurosciencenews.com/sleep-amyloid-beta-8238/
Lucey, B. P., Hicks, T. J., McLeland, J. S., Toedebusch, C. D., Boyd, J., Elbert, D. L., Patterson, B. W., Baty, J., Morris, J. C., Ovod, V., Mawuenyega, K. G., & Bateman, R. J. (2017, December 8). Effect of sleep on overnight CSF amyloid-beta kinetics. Annals of Neurology. Retrieved on December 28, 2017 from http://onlinelibrary.wiley.com/doi/10.1002/ana.25117/full