Researchers at the University of Warwick in England conducted an analysis of sleep and cognitive data from 3,968 men and 4,821 women who took part in the English Longitudinal Study of Aging (ELSA). The participants reported on the quality and quantity of sleep over a one-month period.
According to the researchers, they found an association between both quality and duration of sleep and brain function, which changes with age.
In adults between the ages of 50 and 64, short sleep (less than six hours a night) and long sleep (more than eight hours a night) were associated with lower brain function scores. In older adults between the ages of 65 and 89, lower brain function scores were only observed in long sleepers, the researchers reported.
“Six to eight hours of sleep per night is particularly important for optimum brain function in younger adults,” said Dr. Michelle A. Miller.
“These results are consistent with our previous research, which showed that six to eight hours of sleep per night was optimal for physical health, including lowest risk of developing obesity, hypertension, diabetes, heart disease, and stroke.”
She noted that researchers found it interesting that in younger, pre-retirement-aged adults, sleep quality did not have any significant association with brain function scores, while in adults older than 65, there was a significant relationship between sleep quality and the observed scores.
“Sleep is important for good health and mental well-being,” said researcher Francesco Cappuccio, M.D. “Optimizing sleep at an older age may help to delay the decline in brain function seen with age, or indeed may slow or prevent the rapid decline that leads to dementia.”
“If poor sleep is causative of future cognitive decline, non-pharmacological improvements in sleep may provide an alternative low-cost and more accessible public health intervention to delay or slow the rate of cognitive decline,” concluded Miller.
The study was published in the online journal PLOS ONE.
Source: University of Warwick