A new study has found that the less older adults sleep, the faster their brains age. These findings, relevant in the context of Singapore's rapidly ageing society, pave the way for future work on sleep loss and its contribution to cognitive decline, including dementia.
Past research has examined the impact of sleep duration on cognitive functions in older adults. Though faster brain ventricle enlargement is a marker for cognitive decline and the development of neurodegenerative diseases such as Alzheimer's, the effects of sleep on this marker have never been measured.
The Duke-NUS study examined the data of 66 older Chinese adults, from the Singapore-Longitudinal Aging Brain Study(1). Participants underwent structural MRI brain scans measuring brain volume and neuropsychological assessments testing cognitive function every two years. Additionally, their sleep duration was recorded through a questionnaire. Those who slept fewer hours showed evidence of faster ventricle enlargement and decline in cognitive performance.