In mice, the researchers found that sleep deprivation boosted the levels of the protein, which builds up in plaques.
If a person is awake for a long time, levels of the protein might build up, Holtzman said. This could play a role in middle age because Alzheimer's disease begins to clog the brain several years before symptoms become apparent.
Dr. Nikolaos Scarmeas, an associate professor of neurology at Columbia University Medical Center in New York City, said the findings are "very impressive, extremely valid and useful."
Researchers have linked sleep problems and Alzheimer's disease before, he said, but from the perspective of the sleep problems being a symptom of the illness and a result of aging. The idea that sleep deprivation might cause Alzheimer's deserves more attention, Scarmeas said.
Holtzman said that future research should investigate how processes in the brain can be manipulated with drugs so that people get more sleep and less brain clogging.
For now, though, his advice is short and simple: "Get enough sleep in middle age."
The Alzheimer's Association has more about Alzheimer's disease.
SOURCES: David M. Holtzman, M.D., chairman, neurology, and associate director, Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis; Nikolaos Scarmeas, M.D., associate professor, neurology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York City; Sept. 24, 2009, Science, online
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