In a small study, researchers discovered that thinner participants with breathing problems during sleep were more likely to have biological signs of an increased likelihood of developing Alzheimer's. / BananaStock
Sleep apnea, the condition that robs sufferers of deep sleep by endlessly and subconsciously waking them up, becomes more common as people age. Now, a small new study raises the possibility that it may somehow cause — or be caused by — Alzheimer's disease.
Don't worry just yet if you have sleep apnea. The research is preliminary, and it's possible that there may be no connection between the two conditions. Still, scientists found that slimmer seniors with signs of disrupted breathing during sleep were more likely to have indicators of developing Alzheimer's disease.
"This is just a correlation," said study lead author Dr. Ricardo Osorio, a research assistant professor at the New York University School of Medicine, in New York City. But, he said, the prospect of a connection deserves further study since there may indeed be a link between sleep, aging and memory, which severely declines in Alzheimer's patients.
"It's clear that sleep is important for memory, and sleep changes as you get older," he said. "Disrupted breathing during sleep also increases with aging."
People who have sleep apnea often don't know it. They have trouble staying in deep sleep because their throats close as they slumber, temporarily blocking their airways and requiring them to subconsciously wake up to get air. Some sleep apnea sufferers may awaken 35 or more times an hour.
In the new study, researchers tested the sleep of 68 seniors in their 60s, 70s and 80s. Their average age was 71.
A quarter of them had symptoms of moderate to severe breathing problems during sleep (a sign that they may have sleep apnea), and about 49 percent had mild breathing problems. But none of them complained of sleepiness or concentration problems, which sleep apnea can cause, Osorio said.
The researchers discovered that thinner participants with breathing problems during sleep were more likely to have "biomarkers" — biological signs — of an increased likelihood of developing Alzheimer's. These signs indicate brain damage and decreased use of glucose (the sugar that blood transports) in the brain, Osorio said.
"We do not know if these people will develop Alzheimer's in the future, and we don't know how much risk they have," he said.
