A preliminary study has discovered that the loss of one night's sleep in healthy young men may lead to an increased risk of developing Alzheimer's disease.
The study, published in Neurology, the medical journal of the American Academy of Neurology, indicated that the loss of one night's sleep may increase the risk of developing Alzheimer's disease because it raises the levels of tau protein in healthy young men's blood.
Study author Dr. Jonathan Cedernaes, a neurologist at Uppsala University in Sweden, said: "Our exploratory study shows that even in young, healthy individuals, missing one night of sleep increases the level of tau in blood suggesting that over time, such sleep deprivation could possibly have detrimental effects."
The Alzheimer's Association defines tau as a protein that helps stabilize the internal makeup of brain nerve cells and an abnormal form of tau builds up in Alzheimer's and causes the interior of the cell to fall apart.
When these abnormal tau proteins clump together, they form "tangles" which are a key sign of Alzheimer's, frontal lobe dementia and Lewy body disease.
During sleep, tau and other toxins in the brain are cleared away and when a person loses sleep or has disordered sleep, it can interfere with the brain's ability to clean up these toxins.
Mayo Clinic neurologist Dr. Donn Dexter said: "When you get more of that deep sleep and you get the REM sleep in the normal amounts, that improves clearance of abnormal proteins which we think is good."
However, the researchers warned that the study is small and inconclusive, and acknowledged that they were not able to determine what the increased levels might mean.
Cedernaes said: "Higher levels in the blood may reflect that these tau proteins are being cleared from the brain or they may reflect elevated tau levels in the brain. Future studies are needed to investigate this further."
