‘Disturbed’ sleep patterns potential sign of Alzheimer’s

● Researchers show body clock disruptions occur years before illness

Doctors could identify people at risk of Alzheimer’s disease earlier through disruption to their sleeping patterns, according to new research.

New findings show that disturbances in the sleep/wake cycle occur sooner in people whose memories are intact but their brain scans show early preclinical evidence of Alzheimer’s. Early detection is important as Alzheimer’s damage can take root in the brain 15 to 20 years before clinical symptoms first appear.

Researchers at Washington University School of Medicine, tracked circadian rhythms – a person’s internal body clock, in 189 older adults with an average age of 66. Some had positron emission tomography (PET) scans to look for Alzheimer’s-related amyloid plaques in their brains. Others had their cerebrospinal fluid tested for Alzheimer’s-related proteins. Some had both scans and spinal fluid testing.

Of the participants, 139 had no evidence of the amyloid protein that signifies preclinical Alzheimer’s. Most had normal sleep/wake cycles, although several had circadian disruptions linked to advanced age, sleep apnea or other causes.

But among the other 50 subjects, who either had abnormal brain scans or abnormal cerebrospinal fluid, all experienced significant disruptions

0 Tracking sleep patterns could offer an indication of if someone is likely to develop Alzheimer’s in their internal body clocks, determined by how much rest they got at night and how active they were during the day. Disruptions in the sleep/ wake cycle remained after the researchers statistically controlled for sleep apnea, age and other factors.

By tracking activity during day and night, researchers could tell how scattered rest and activity were in 24-hour periods. Subjects who experienced short spurts of activity and rest during day and night were more likely to have evidence of amyloid build-up in their brains.

Dr David Reynolds, at Alzheimer’s Research UK, said: “Research has faced a bit of a chicken and egg situation when looking at links between sleep and dementia. While we know people with Alzheimer’s experience disturbed sleep patterns, whether this contributes to the disease or is an early consequence has been unclear.

“This study observes changes in daily rest and activity patterns at an early stage, where people are showing signs of Alzheimer’s in the brain before symptoms begin.”