People in early middle age who have poor sleep quality, including having difficulties falling or staying asleep, have greater indicators of poor brain health in late middle age, according to a study published in the October 23, 2024, online issue of Neurology. The study does not establish that insufficient sleep accelerates brain aging. It only demonstrates a link between poor sleep quality and symptoms of brain aging.
“Sleep problems have been linked in previous research to poor thinking and memory skills later in life, putting people at higher risk for dementia,” stated study author Clémence Cavaillès, Ph.D., of the University of California San Francisco.
“Our study which used brain scans to determine participants’ brain age, suggests that poor sleep is linked to nearly three years of additional brain aging as early as middle age.”
The study included 589 persons with an average age of 40 at the start of the trial. Participants completed sleep surveys both at the beginning of the trial and again five years afterward. Participants underwent brain scans 15 years after the trial began.
Researchers analyzed individuals’ responses to queries such as, “Do you usually have trouble falling asleep?” “Do you typically get up several times at night?” and “Do you usually wake up far too early?” They recorded the amount of six poor sleep characteristics for each participant: short sleep duration, terrible sleep quality, difficulties falling asleep, difficulty staying asleep, early morning wakeup and daytime drowsiness.
Participants were separated into three groups. The low group members lacked more than one bad sleeping habit. People in the intermediate group had two to three, and those in the high category had more than three. At the start of the study, around 70% were in the low group, 22% were in the medium and 8% were in the high group.
Researchers studied participants’ brain scans where the level of brain shrinkage corresponds to a given age. Researchers employed machine learning to assess the brain age for each individual.
After correcting for characteristics such as age, sex, high blood pressure and diabetes, researchers discovered persons in the middle group had an average brain age that was 1.6 years older than those in the low group, while those in the high group had an average brain age 2.6 years older.
Of the sleep characteristics, terrible sleep quality, trouble falling asleep, difficulty staying asleep and early morning wakeup were connected to increased brain age, especially when participants regularly had these poor sleep characteristics across five years.
“Our findings highlight the importance of addressing sleep problems earlier in life to preserve brain health, including maintaining a consistent sleep schedule, exercising, avoiding caffeine and alcohol before going to bed and using relaxation techniques,” said author Kristine Yaffe, MD, of the University of California San Francisco and a member of the American Academy of Neurology.
“Future research should focus on finding new ways to improve sleep quality and investigating the long-term impact of sleep on brain health in younger people.”
A weakness of the study was that individuals reported their own sleep issues and it is conceivable they may not have reported them accurately.
A study published in Neurology indicated that poor sleep quality in early middle age is connected to indications of brain aging later in life. Researchers monitored 589 patients over 15 years, using sleep questionnaires and brain scans to measure brain age. Those with poor sleep—such as problems getting or staying asleep—showed brain aging up to 2.6 years older than those with better sleep. The study proposes addressing sleep disorders early to safeguard brain health, while it does not show that inadequate sleep actually causes brain aging. Researchers urge more studies to promote sleep and study its long-term impacts.
