Just as a single night of insomnia may leave you feeling groggy and cranky, solid slumber can help you feel rested and ready to take on the day. How well you sleep over time, however, can influence deeper aspects of your health and well-being, new research shows.
Five distinct sleep patterns are tied to your health, lifestyle and cognition and even how different regions of your brain connect to one another, according to a study published Tuesday in the journal PLOS Biology.
Specifically, those “sleep-biopsychosocial profiles” encompass biological, psychological and socioenvironmental factors — such as having a safe, comfortable place to sleep — that contribute to your sleep hygiene.
Much of sleep medicine research focuses on specific problems, such as sleep apnea’s link to cognitive decline, how insomnia affects the heart or whether someone is a night owl or an early bird. The new study, led by researchers at Concordia University in Montreal, looked at the bigger picture.
“People should treat their sleep seriously,” said study co-author Valeria Kebets, manager of machine learning projects at Concordia’s Applied AI Institute. “It affects everything in their daily functioning.”
To define the profiles, researchers analyzed the sleep data of 770 “healthy” young adults ages 22 to 36, indicating they had not been diagnosed with a psychiatric condition, such as bipolar disorder, Kebets said. The data came from the Human Connectome Project, an existing database that studies brain connectivity.
Using a questionnaire called the Pittsburgh Sleep Quality Index, participants self-reported their sleep characteristics for the previous month.
They also underwent functional MRI, a type of scan that maps brain activity.
“It’s important to look at all these different aspects of sleep, all the different dimensions of sleep, because they’re related to different outcomes and they can also be improved by different interventions,” Kebets said.
Next, Kebets and her team analyzed 118 biopsychosocial measures, such as cognition, substance use, demographics and personality.
Someone may fall into more than one of the five categories Kebets and her team identified, especially over time, she said.
For example, if you’re going through a stressful few months at work, the associated sleep disruptions may temporarily align you with a different profile.
“These are profiles that we all show to a certain degree,” Kebets said.
The researchers identified two general and three specific sleep profiles.
No. 1: Poor sleep and mental health
Characteristics include decreased sleep satisfaction, longer time to fall asleep and greater complaints of sleep disturbances.
People with this pattern of poor sleep experienced daytime impairment and negative emotions, including fear, stress and anger. In addition, people in this group showed worse mental health, such as depression, anxiety and internalizing behavior.
Previous research has shown the association between sleep and mental health.
“Bad sleep begets poor mental health,” said J. Todd Arnedt, director of the Behavioral Sleep Medicine Program and co-director of the Sleep and Circadian Research Laboratory at the University of Michigan Medical School, who wasn’t involved in the study. “Poor mental health begets bad sleep.”
No. 2: Sleep resilience and mental health
People in the second profile also reported negative emotions, including sadness, and poor mental health, namely attention difficulties such as inattention and attention-deficit/hyperactivity disorder. Low conscientiousness was another attribute.
People in this group who experienced daytime impairments didn’t complain of any sleep difficulties, however. Researchers called the phenomenon “sleep resilience.”
It’s possible that people who fit this profile had sleep issues they were unaware of, Kebets said, calling it “sleep misperception.”
“Sometimes when you have some mental health issues — symptoms of anxiety or depression, for instance — maybe you’re not sleeping as well as usual, but you’re not necessarily acknowledging it because you have other stuff on your mind,” Kebets said.
No. 3: Sleep aids and sociability
The third profile represents people who took hypnotics, or sleep aids, to get a good night’s rest.
People in this group reported social satisfaction, including friendship and emotional support. They also experienced less perceived rejection and fewer attention problems.
However, this profile was also characterized by worse emotional recognition, the ability to identify others’ emotions, and visual episodic memory, the ability to vividly recall past experiences.
No. 4: Sleep duration and cognition
People who reported sleeping fewer than six to seven hours a night had lower agreeableness and higher aggressive behavior.
What’s more, people who slept little showed cognitive consequences. For example, they performed tasks involving emotional processing and fluid intelligence, which is a measure of problem-solving, with worse accuracy.
No. 5: Sleep disturbances, cognition and mental health
Sleep disturbances including pain, breathing issues, frequent urination, temperature imbalance and multiple awakenings are indicators of the fifth profile.
People in this group experienced substance abuse and poor mental health, such as thought problems and anxiety. They also demonstrated aggressive behavior and worse cognitive performance, including language processing.
Sleep critical to mind-body health
There were several major limitations to the research. Participants were overwhelmingly white, healthy, young adults who were working full time. In addition, researchers noted that “a large number of” participants were siblings, even twins.
The study also analyzed people’s sleep behavior for only a month. The five sleep profiles represent a snapshot in time, Arnedt said. “If you looked at these same people a year later, they may fall in totally different categories.”
He also noted that the study was retrospective, meaning it looked at how participants had slept in the past. Having people keep sleep diaries in real time is a preferred method of studying sleep.
However, by identifying individual sleep profiles, the findings could help sleep clinicians develop personalized treatment approaches, said Dr. Phyllis Zee, director of the Center for Circadian and Sleep Medicine at the Northwestern University Feinberg School of Medicine and medical director of the Northwestern Medicine Sleep Disorders Center.
“We really need to consider multiple sleep profiles in our research and clinic — the value of a multidimensional approach to data,” Zee, who wasn’t involved with the new research, said in an email.
Dr. Rafael Pelayo, a clinical professor in the division of sleep medicine at the Stanford University School of Medicine, also praised the study’s holistic approach. The five profiles, he said, may help predict who’s at risk of developing sleep problems.
It’s critical that everyone, not just health care providers, understands the multidimensional nature of sleep, said Pelayo, who wasn’t involved in the research.
“Sleep is a more complex issue than just how much time you spend in bed,” he said. “If I can improve your sleep, it has downwind effects on your overall health — not just your mental health, but your physical health.”
The new research adds to strong evidence that sleep is essential for brain and body health. Sleep disturbances, Zee said, increase the risk of problems, including mood disorders, immune issues and neurodegeneration, as in Alzheimer’s and Parkinson’s diseases.
The bottom line, Pelayo said, is that the research reinforces that hope and help are available for people with sleep difficulties: “Nobody should be condemned to sleep poorly the rest of their lives.”