A new study to be published in the Archives of Neurology reports levels of amyloid beta, a byproduct of brain activity considered a marker in Alzheimer’s disease, normally rises during the day and decreases at night. Authors of the study suggest a possible link between sleep deprivation and people’s risk for developing dementia such as Alzheimer’s.
It is well established that reduced sleep can lead to cognitive dysfunction. However, prolonged sleep disturbance may play a role in pathologic processes underlying disease.
The authors indicate that levels of amyloid beta increase and decrease naturally. In healthy people, levels of the protein drop to their lowest level about six hours after sleep and then return to their highest levels six hours after peak wakefulness. The transition from sleep to wakefulness strongly correlated with the rise and fall of amyloid beta. The relationship was most pronounced in healthy, young people and less so in older adults who suffer shorter or more prolonged periods of disrupted sleep.
The authors suggested that the brain’s low activity during sleep allows the body to clear amyloid beta through the spinal fluid. Levels of the protein in Alzheimer’s patients, however, appear to be constant. The authors note that more research is needed, but there are reasons to believe that better sleep may be helpful in promoting brain health and reducing risk of Alzheimer’s disease. Sleep may be a factor in the known relationship between exercise and reduced risk of Alzheimer’s as sleep is related to enhanced sleep.