Sleep and aging
Sleep patterns significantly affect how aging progresses. Its impairments are associated with an increased risk of depression, deterioration of cognitive functions (impaired attention, thinking ability, learning, problem solving), and the development of cardiovascular diseases.
Poor sleep is one of the risk factors for dementia, and normalizing sleep can prevent the development of dementia. For this reason, scientists are paying close attention to research on the effects of sleep on brain health. The authors of the new study compared sleep characteristics of older adults with indicators of biomarkers for dementia risk and cognitive health.
Sleeping well reduces the risk of dementia and depression
In the study, scientists analyzed data obtained from a survey of 4417 people aged 65-85 years. All of them underwent positron emission tomography (PET) to detect deposits of amyloid beta protein in the brain. This protein is currently considered a marker for the progression of Alzheimer’s disease. With her, this protein begins to be deposited in the tissues of the brain in the form of plaques. However, it can also be found in some healthy elderly people. Previously, scientists have hypothesized that sleep may help limit the synthesis of beta-amyloid, as well as improve its clearance from the brain.
In the study participants who slept a little (according to the study’s criteria – less than six hours a night) or a lot (more than nine hours), scientists found more signs of depression and cognitive impairment than those who slept the recommended amount of time (seven to eight hours).
The sleep pattern was also associated with deposits of beta-amyloid in the brain: against the background of lack of sleep, there were more of them than during normal sleep. However, sleeping for more than nine hours a day did not increase the amount.
Of the lifestyle factors, alcohol consumption influenced sleep duration. The more often the participants drank, the more they slept. At the same time, the amount of caffeine consumed during the day was not associated with sleep duration. Scientists also found that women and people who studied for more years slept longer.
“The main conclusion is that it is important to maintain a healthy sleep pattern in the second half of life. Additionally, people who do not sleep enough or too much are more likely to be overweight and have symptoms of depression, ”said CNN Joe Winer of Stanford Universitya, co-author of the study.