Got seven or more hours of sleep, but still woke up feeling irritable, sluggish, and tired? You’re not the only one: Fewer than 1 in 3 Americans are getting the right of kind of sleep that leaves them feeling refreshed, energetic, and alert the next morning, a new study has found.
An international team of researchers, led by physicians at Brigham and Women’s Hospital, analyzed various measures of “restorative sleep” in a nationally representative survey of more than 1,000 US adults. Respondents were asked to complete a nine-question survey in the fall of 2021, assessing their mood and energy levels following the previous night’s sleep on a five-point scale.
Although previous research has indicated that two-thirds of Americans are getting the expert-recommended seven to nine hours of sleep, just 28 percent of participants in this study reported high scores of restorative sleep, meaning they woke up with improved alertness, cognitive function, mood, and energy.
The results were published this month in the journal Frontiers in Sleep.
Lead author Dr. Rebecca Robbins, a sleep scientist at Brigham and Women’s Hospital and an instructor in medicine at Harvard Medical School, said she was surprised to discover so many Americans struggle with getting good sleep despite spending enough time in bed.
“What that tells us is that sleep duration is part of the equation, but it’s not everything,” she said. “We really need to be drawing more attention to some of these qualitative metrics for a full understanding of sleep.”
People 60 and older were more likely to have restorative sleep than young adults, the study found, as were widowers and retirees, compared with married people and paid employees, respectively.
Renting a home, joblessness, and living with three or more people were associated with lower odds of restorative sleep.
Study author Dr. Stuart Quan, a sleep medicine professor at Harvard Medical School and a physician at Brigham and Women’s Hospital, noted older adults typically have a harder time falling and staying asleep due to physiological changes that affect their sleeping patterns.
One explanation for this apparent contradiction with the results of the study, Quan said, may be social factors allowing older adults, who to tend to be retired, to feel more well rested than their younger, working-age counterparts.
“They’re more settled in. They don’t have to worry about getting up for work,” Quan said. “Basically the adverse physiology is being outweighed by the social vicissitudes of life.”
Likewise, renters and unemployed people may struggle getting a good night’s sleep due to their social and financial circumstances.
“There are just more stressors in their lives or more uncertainties,” Robbins said. “Those conditions certainly present concerns and anxieties that can increase our risk for poor mental health and sleep-related difficulties, therefore hindering our ability to obtain restorative sleep.”
The study did not detect any statistically significant differences in restorative sleep patterns by gender, contrary to previous research showing that sleep difficulties and disorders, like insomnia, are more prevalent among women.
Robbins said many Americans’ difficulty sleeping may be attributed to the COVID-19 pandemic. During the early stages of the pandemic, studies showed many adults were getting more sleep, Robbins said, because they were no longer commuting to their workplaces. But as the pandemic wore on, fear and anxiety spiked, Robbins said, and people’s sleep got worse.
“We believe that the early months [of the pandemic] had this kind of protective effect for our sleep health, which was overwhelmingly positive,” she said. “Unfortunately, things took a different tack and we saw increases across the population in insomnia symptoms and insomnia disorder.”
Deanna Pan can be reached at deanna.pan@globe.com. Follow her on Twitter @DDpan.
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