A new study indicates that individuals in early middle age who experience poor sleep quality, such as trouble falling asleep or staying asleep, tend to show more indications of declining brain health as they reach late middle age. However, this research does not establish that inadequate sleep speeds up brain aging; it merely points out a correlation between sleep difficulties and brain aging indicators.
According to a study published in the online edition of Neurology® on October 23, 2024, those in early middle age who struggle with sleep quality, encompassing challenges with both falling and remaining asleep, exhibit more signs of declining brain health as they move into late middle age. It is important to note that this study does not confirm that poor sleep directly accelerates brain aging; it highlights a connection between sleep issues and signs of an aging brain.
“Previous studies have connected sleep issues with diminished cognitive abilities and memory as people grow older, which increases their chances of developing dementia,” noted Clémence Cavaillès, PhD, from the University of California San Francisco, the study’s author. “Our research, which utilized brain imaging to assess participants’ brain age, implies that poor sleep may correlate with almost three additional years of brain aging starting in midlife.”
The study observed 589 participants, averaging 40 years old at the beginning of the research. They completed sleep questionnaires at the start and again five years later. Brain scans were conducted 15 years after the study commenced.
Researchers analyzed participants’ answers to questions like, “Do you typically have trouble falling asleep?” “Do you often wake up multiple times during the night?” and “Do you generally wake up much too early?” They tracked six characteristics of poor sleep for each individual: short sleep duration, low sleep quality, problems falling asleep, issues staying asleep, waking early, and daytime drowsiness.
The participants were categorized into three groups: the low group, which had at most one poor sleep characteristic; the middle group, which had two to three; and the high group, which exhibited more than three. Initially, around 70% belonged to the low group, 22% to the middle, and 8% to the high group.
The researchers assessed participants’ brain scans, where the degree of brain shrinkage corresponds to a specific age. They applied machine learning techniques to establish the brain age of each participant.
After accounting for variables such as age, gender, high blood pressure, and diabetes, they discovered that individuals in the middle group had an average brain age 1.6 years older than those in the low group, while those in the high group had, on average, a brain age 2.6 years older.
Among the various sleep characteristics, poor sleep quality, trouble falling asleep, difficulty staying asleep, and waking up early were notably associated with an older brain age, particularly when individuals consistently experienced these sleep issues over the span of five years.
“Our findings underscore the significance of addressing sleep issues early in life to safeguard brain health. This includes maintaining a steady sleep schedule, exercising regularly, avoiding caffeine and alcohol prior to bedtime, and employing relaxation techniques,” commented Kristine Yaffe, MD, from the University of California San Francisco and a member of the American Academy of Neurology. “Future studies should explore new methods to enhance sleep quality and examine the long-term consequences of sleep on brain health in younger individuals.”
It is worth noting a limitation of the study: participants reported their own sleep issues, which might not have been accurately presented.
