Shortness of sleep speeds up the aging of the brain in older people, say researchers from Duke-NUS Graduate Medical School Singapore.

The research on healthy adults aged 55 years and older, published in the journal Sleep, used magnetic resonance imaging (MRI) and neuropsychological assessment to investigate changes in the brain associated with aging.

For every hour of reduced sleep duration, the researchers found an incremental annual expansion of the brain ventricles and an annual incremental decline in global cognitive performance.

“Though faster brain ventricle enlargement is a marker for cognitive decline and the development of neurodegenerative diseases such as Alzheimer’s,” the researchers say, “the effects of sleep on this marker have never been measured.”

The research paper’s results therefore add new evidence: “Each hour of reduced sleep duration at baseline augmented the annual expansion rate of the ventricles by 0.59%, and the annual decline rate in global cognitive performance by 0.67% in the subsequent 2 years, after controlling for the effects of age, sex, education and body mass index.”