According to a recent Chinese study, the time people go to bed and the amount of sleep time may be a sign of cognitive decline and an increased risk of developing dementia.
Analysis of data from 1.982 participants aged 60+ years showed that risk of dementia was 69% higher in those who slept for more than 8 hours (compared to 7-8 hours) and 2-times higher for those who went to bed before 9 PM (compared to 10 PM or later).
The major risk group turned to be men and participants aged between 60 and 74 years old.
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