Long Sleep, Turning In Early May Up Risk for Dementia
Too much sleep and time in bed (TIB) may raise the risk of developing dementia and Alzheimer's disease (AD), new research suggests. Results from a population-based study of almost 2000 older adults, all of whom were free of dementia at baseline, showed that risk for dementia was 69% higher in those who slept more than 8 hours daily vs 7 to 8 hours daily; and it was twice as high for those who went to bed before 9 PM vs at 10 PM or later
@elaine The researchers note that sleep quantity, quality, and circadian rhythm change as individuals age. Previous studies have suggested that extreme sleep duration, sleep fragmentation, and excessive daytime sleepiness are associated with cognitive decline or dementia. However, the association of TIB — a composite indicator of sleep duration, latency, and fragmentation — with dementia is "poorly understood," the investigators write. The longitudinal association of sleep timing with dementia and cognitive decline in older adults "has rarely been explored," and most studies have investigated White populations in North America and Europe rather than rural adults in China, the investigators note.