We know that getting the right amount of sleep is important for both our bodies and brains. But, nearly 60 percent of older adults have some kind of chronic sleep disturbance, often sleeping less deeply, waking more frequently at night, or awaking too early in the morning.

Risk for Alzheimer’s disease increases with age, and scientists are discovering a connection between sleep—good or bad—and Alzheimer’s. The disease, an illness of the brain that inhibits communication between brain cells, affects how well a person can remember, think clearly and use good judgment.

“...poor sleep may lead to abnormal amounts of beta-amyloid in the brain...”

What’s the connection between sleep and Alzheimer’s?

We long believed that the initial build-up of beta-amyloid protein in the brain—the same protein involved in Alzheimer’s disease—caused poor sleep. However, more recent studies reveal that poor sleep may lead to abnormal amounts of beta-amyloid in the brain, which in turn can lead to the build-up of the amyloid plaques characteristic of Alzheimer’s disease. Such neurodegenerative changes can affect sleep-related brain regions. So perhaps it’s not a question of which comes first. Rather how do poor sleep and Alzheimer’s disease affect one another?

Emerging insights from the lab

Much of what we’re learning comes from animal studies. For example, a study in mice showed that beta-amyloid levels naturally rose during wakefulness and fell during sleep. Mice deprived of sleep showed significantly greater beta-amyloid plaques than those that slept normally. Increasing sleep had the opposite effect—it reduced the amyloid load.

The bottom line: while research suggests that poor sleep is a risk factor for Alzheimer’s disease, there currently is no evidence that improving sleep will reduce the likelihood of developing the disease. Nor does research indicate that sleep medications will reduce the risk for Alzheimer’s.

Until we know more, finding ways to get a good night’s sleep just makes good sense.