How too little (or too much) sleep affects dementia risk

People with Alzheimer’s may begin to experience symptoms in their 60s or 70s, but amyloid may begin to accumulate Twenty years earlier. That’s why it’s important to get seven to nine hours of sleep a night starting in your 40s or 50s, or even earlier, said Joe Winer, a postdoctoral fellow in neurology and neuroscience at Stanford University’s Center for Sleep and Circadian Science.

“We don’t have good answers yet, like, does your sleep in your 20s affect your risk later in life?” Winer said. “But I think these indications are that in midlife, when you’re approaching your 60s and 70s, your sleep is going to be really important.”

Some sleep disorders, especially sleep apnea, have also been linked to an increased risk of dementia. This may be because sleep apnea disrupts people’s sleep or because it tends to occur in people who are overweight or have diabetes, which are also linked to dementia.

But even after accounting for these other problems, sleep apnea appears to pose an independent risk for dementia, said Diego Carvalho, MD, assistant professor of neurology at the Mayo Clinic Sleep Medicine Center. Restricting oxygen Once it reaches the brain, it increases brain inflammation and damages blood vessels and cells.

Sleeping too much

On the other hand, too much sleep can also cause Link There is an increased risk of developing dementia, although the effect may be more indirect.

If a person regularly spends more than nine hours in bed each night or takes multiple naps during the day, this may be a sign that they are having poor sleep quality, which could increase their risk of Alzheimer’s disease for the reasons listed above.

Alternatively, needing too much sleep may be associated with mental or physical disabilities. Mental health conditions, such as depression, and physical health conditions, such as diabetes or cardiovascular problems, are Linked to higher risk of dementiaas does physical inactivity, loneliness and isolation.

“Right now, there is no clear evidence for a relationship between long sleep and dementia,” Carvalho said. “It may be more of a symptom of an underlying problem rather than a cause of it.”

Early symptoms?

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The first areas of the brain to be affected by Alzheimer’s disease are those that contribute to Regulating sleep and circadian rhythmsAs a result, people with the condition may have sleep problems even before they experience memory loss or other symptoms.

Besides amyloid, the other major protein thought to cause Alzheimer’s disease is tau. Like amyloid, tau accumulates in the brain and eventually damages brain cells. One of the first places tau appears is “in these brainstem regions that are important for regulating sleep and wakefulness,” Winer said. “So we think that tau showing up very early in these areas disrupts people’s sleep-wake cycles.”

Sleep problems can also be an early sign of other common dementias. In Lewy body dementia and Parkinson’s disease dementia, for example, REM sleep can sometimes be disrupted, causing people to act out in their dreams — something your bed partner might notice, Seshadri says.

Experts say it’s normal for older people to sleep a little more or a little less after retirement, and to wake up and go to bed earlier or later than before. But if the changes are drastic, consider seeing a doctor or sleep specialist.

The New York Times

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