New research published in the Journal of the American Geriatrics Society suggests that the time people go to bed and the amount of time they sleep may affect their risk of developing dementia.
In the study of 1,982 older adults in China who were free of dementia at the start of the study, 97 participants were diagnosed with dementia during an average follow-up of 3.7 years.
Risk of developing dementia was 69% higher in those who slept for more than 8 hours (versus 7-8 hours) and 2-times higher for those who went to bed before 9 p.m. (versus 10 p.m. or later).
“This suggests that cognitive function should be monitored in older adults who report prolonged time in bed and advanced sleep timing,” the authors wrote.
The researchers found that the associations of sleep problems with greater cognitive decline are evident only among older people aged 60–74 years and men.