Sleep is crucial for healthy brain function. Too little sleep can make it much harder for people to think clearly the following day. People who sleep less than six hours nightly have impaired judgment and slower reflexes. What’s more, older adults who don’t get enough sleep have more beta-amyloid in their brains. This is a protein associated with Alzheimer disease. Now, however, scientists say that sleeping too much may signal a heightened risk for dementia.
What Is the Link Between Sleep and the Risk for Dementia?
The data were collected as part of the Framingham Heart Study. Almost 2,500 older adults taking part in the study were asked how long they slept every night.
During the ten-year follow-up, 234 of them developed signs of dementia. Statistical analysis showed that those who slept more than nine hours a night were at double the risk of such a diagnosis.
Lower Education Raises the Risk:
This was particularly marked among those who never finished high school. Long sleepers with less education were at six times the risk for dementia as other study volunteers.
The researchers believe that long sleep duration is probably a marker rather than a cause of dementia. They suggest it could be used as a screening tool.
Westwood et al, Neurology, online Feb. 22, 2017
What Can You Do?
We will be more interested in screening for future dementia if there is something we can do today to prevent it. Dutch scientists have been looking at lifestyle factors that could predict the risk for dementia (Schiepers et al, International Journal of Geriatric Psychiatry, online Feb. 28, 2017). These factors do not seem to apply to very old individuals, however (Deckers et al, Aging & Mental Health, online Feb. 2, 2017).
For now, it seems that focusing on behaviors that keep our hearts healthy can also help our brains (Ashby-Mitchell et al, Alzheimer’s Research & Therapy, online Feb. 17, 2017). That means following your mother’s advice to exercise, eat right, don’t smoke and stay in touch with family and friends.
