markers of Alzheimer's (83.7 percent). On average, those with preclinical disease were in bed as long as other participants, but they spent less time asleep. They also napped more often.
"When we looked specifically at the worst sleepers, those with a sleep efficiency lower than 75 percent, they were more than five times more likely to have preclinical Alzheimer's disease than good sleepers," Ju says.
Ju and her colleagues are following up with studies in younger participants who have sleep disorders.
"We think this may help us get a better feel for the way this connection flows — does sleep loss drive Alzheimer's, does Alzheimer's lead to sleep loss, or is it a combination?" Ju says. "That will help us determine whether we can change the course of disease with pharmaceuticals or other treatments."