The worse your sleep, the more likely you may be to develop Alzheimer's disease, a recent study finds. Specifically the study found that if people wake up often during the night, more than five times in an hour, they are more likely to have preclinical Alzheimer's disease. The study is preliminary. It finds an association, but not a cause and effect. The study evaluated 100 men and women aged 45-80. All were free of dementia at the study start. Half of them have a family history of Alzheimer's disease. For 14 days, the men and women wore a device that measures sleep. They also completed sleep diaries and questionnaires. The researchers analyzed spinal fluid. They looked at brain scans. They were looking for indicators of "amyloid plaques." These are deposits found in the brains of people with Alzheimer's. Experts believe the deposits can begin forming 10 to 15 years before the symptoms appear. People slept an average of six-and-a-half hours, although they spent about eight hours a night in bed.
Sleep Problems and Alzheimer's: Study Results About 25% of the 100 people had evidence of pre-clinical Alzheimer's disease due to abnormal indicators reflecting amyloid plaques. Those who woke up most frequently, more than five times an hour, were more likely than the others to have these abnormal biomarkers. Those who spent less than 85% of their time in bed actually sleeping were also more likely to have preclinical Alzheimer's disease, they found. About half of the group had more than five awakenings an hour, and about half spent less than 85% of their time in bed sleeping. The study was funded by the nonprofit Ellison Medical Foundation and the National Institutes of Health. This study is due to be presented at a medical conference. The findings should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.