Sleeplessness May Harm Aging Brain

Brains of sleepless elderly people showed similarities to Alzheimers patients in new study

(RxWiki News) When people don't get enough sleep, they might complain about not having a clear mind. A lack of shut-eye also may affect their mind in other ways.

According to a new study, the brains of older people who do not sleep long enough or whose sleep is not restful may show similar physical signs as the brains of those diagnosed with Alzheimer's disease.

"Try to get a good night's rest every night."

Adam Spira, PhD, of the Bloomberg School of Public Health at Johns Hopkins University, was the lead author of this study.

Dr. Spira and his research team analyzed the brain images of 70 adults who, based on their self-reporting, slept from less than five hours to more than seven hours per day. The average age of the group — which was made up of participants in the Baltimore Longitudinal Study of Aging — was 76.

None of the study participants had a physical disability, difficulty walking, impaired thinking or memory or any major disease other than high blood pressure that was being treated. They were not taking antibiotics, antihistamines, immunosuppressants, steroids or medications to ease chronic pain.

Study participants answered questions about how often they had trouble falling asleep, woke up during the sleep cycle or had trouble getting back to sleep.

Of the 70 study participants, 24 people reported that they slept less soundly and for less time showed signs of abnormal build-up of plaque in the brain's cortex, or outer layer, researchers concluded. Sixteen study participants, researchers wrote, showed signs of abnormal plaque in their brain's precuneus region, which controls certain aspects of eyesight and memory.

Abnormal plaque build-up also has been discovered on the brains of people diagnosed with Alzheimer's disease — the most common form of dementia.

"We found no association between waking several times and [plaque build-up]," the researchers wrote. "But we found a trend toward an association between greater frequency of difficulty falling asleep and [plaque build-up]."

They also wrote, "Additional studies with objective sleep measures are needed to determine whether sleep disturbance causes or accelerates Alzheimer disease."

Insomnia is common among Alzheimer's patients, the researchers wrote.

"This study comes on the heels of several studies that show increased beta amyloid, which is what the plaques are composed of, is increased in people with less than 7 hours of sleep," Robert S. Rosenberg, DO, leading national expert in sleep medicine practicing at Sleep Disorders Centers of Prescott Valley and Flagstaff, told dailyRx News.

"Another recent study has shown that the brain cleans itself of this toxin while asleep. This is another study that shows the potential link of insufficient sleep and Alzheimer’s," said Dr. Rosenberg.

The study was published online October 21 in JAMA Neurology.

The Intramural Research Program and National Institute on Aging funded the study. Its authors included a researcher who has received contracts from a prescription drug-maker.

Review Date: 
October 21, 2013