Researchers in the U.K. say that poor sleep may well lead to shrinkage of the brain’s gray matter over time. The faster deterioration of three parts of the brain was seen in mostly older adults who had poor sleep quality, though not necessarily too little sleep.
Reports suggests it isn’t clear whether poor sleep causes the changes in the brain, whether a shrinking brain causes poor sleep, or whether a bit of both is occurring. “We spend roughly a third of our lives asleep, and sleep has been proposed to be ‘the brain’s housekeeper,’ serving to restore and repair the brain,” said lead researcher Claire Sexton, a postdoctoral research assistant at the University of Oxford in England. “It follows that if sleep is disrupted, then processes that help restore and repair the brain are interrupted and may be less effective, leading to greater rates of decline in brain volume.”
While a visiting research fellow at the University of Oslo, Norway, Sexton and her fellow researchers gave brain scans to 147 Norwegian adults, average age 54, at the study’s start and an average of 3.5 years later.
At the time of the second scan, the adults also filled out questionnaires about their sleep quality, including how long and how well they slept, how long it took to fall asleep, how much time in bed was spent actually asleep, how often they woke up, how sleepy they were during the day and whether they used sleeping medications. Participants took an average of 20 minutes to fall asleep and slept an average of seven hours a night, the researchers found.
After making adjustments for differences in the participants, physical activity, weight and blood pressure — which have been shown to affect sleep quality — the researchers compared changes in participants’ brain scans and reported their findings in the study titled “Poor sleep quality is associated with increased cortical atrophy in community-dwelling adults” which is published in the Journal Neurology.
