Study finds link between bedtime and dementia risk

A recent study found spending a long time in bed and going to sleep early were associated with an increased risk of dementia.

The study was published in the Journal of the American Geriatrics Society and conducted by a group of researchers from the department of neurology at First Medical University in Jinan, China. For their investigation, researchers sought to better understand the relationship between time in bed (TIB) and dementia.

Almost 2,000 participants aged 60 or older were recruited for the investigation. All participants were dementia free and living in rural communities in western Shangdong, China. Researchers assessed the sleep parameters and cognitive function of each participant using questionnaires and mental examinations before and after the trial period that. At the end of the trial period, which spanned from 2014 to 2018, participants were screened for dementia.

During the follow-up, 97 participants were diagnosed with dementia. The study found a significant association between early bedtime and prolonged TIB and an increased risk of dementia. Risk of dementia was 69 percent higher in those who slept more than eight hours and two times higher for those who went to sleep before 9 p.m. Among those who were free of dementia, researchers found a link between early bedtime and prolonged TIB and greater cognitive decline in men aged 60 to 74.

The study authors concluded that these results indicate that cognitive function should be monitored in older adults who go to sleep early and have prolonged TIB.