Poor quality sleep in 50s, 60s increases risk of Alzheimer's disease

People who report the poor quality of sleep as they age from 50s to 60s are at a higher risk of developing Alzheimer disease later in their life as their brain has more protein tangles, finds a study.

The study was published in the 'Journal of Neuroscience'.

"Insufficient sleep across the lifespan is significantly predictive of your development of Alzheimer's disease pathology in the brain," said Matthew Walker, the study's senior author.

Walker and his colleagues found that adults reporting a decline in sleep quality in their 40s and 50s had more beta-amyloid protein in their brains later in life, as measured by positron emission tomography, or PET.

Those reporting a sleep decline in their 50s and 60s had more tau protein tangles. Both beta-amyloid and tau clusters are associated with a higher risk of developing dementia, though not everyone with protein tangles goes on to develop symptoms of dementia.

"The idea that there are distinct sleep windows across the lifespan is really exciting. It means that there might be high-opportunity periods when we could intervene with a treatment to improve people's sleep, such as using cognitive behavioural therapy for insomnia," said Joseph Winer, one of the researchers.

The 95 subjects in the study were part of the Berkeley Aging Cohort Study (BACS), a group of healthy older adults, some as old as 100 years of age, who have had their brains scanned with PET, the only technique capable of detecting both beta-amyloid tangles and, very recently, tau tangles, in the brain.