A graph of how long Americans sleep is a U-shaped pattern throughout our lives, with age 40 being the lowest point and sleep hours beginning to increase around age 50, they report. researchers at the Medical College of Georgia.
Our sleep efficiency, which basically means how much time we spend sleeping we actually sleep, tends to decrease throughout our lives, but researchers were surprised to find the efficiency stabilized between the ages of 30 and 60, says Dr. Xiaoling Wang, a genetic epidemiologist. at the MCG Institute for Georgia Prevention and corresponding author of the study in the journal Scientific Reports.
True sleep time is difficult to measure in a large database of individuals who provide a representative sample of the country, especially because most assessments are self-reported sleep, says the first author, Dr. Shaoyong Su, also an epidemiologist. Genetics of Georgia Prevention. Institute and first author of the study.
The main innovations of the study include its representative sampling technique, widely inclusive age, and the use of accelerometers to measure movement and have a more objective idea of how much participants slept.
For this study, the researchers used what is considered a representative sample of 200 million Americans: 11,279 participants aged 6 years or older in the National Health and Nutrition Examination Survey, or NHANES, which focuses on in different populations or health issues. Data on these participants were collected between 2011 and 2014, but were published in late 2020, and this is the first time that 24-hour accelerometer data was available in a nationally representative sample.
Participants wore non-dominant wrist accelerometers 24 hours a day for seven consecutive days. Although the device does not directly measure sleep time, the premise is that measuring movement gives you some indication of whether you are asleep or not, says co-author Dr. Vaughn McCall, president of MCG’s Department of Psychiatry and Health Behavior and an expert on insomnia, depression, and suicide.
We have confirmed the above findings based on subjective measurements. People think that children and teenagers sleep later and we have found that. And during the Middle Ages, people sleep less and our results are objective. In addition, sleep duration increases for people over 60. “
Shaoyong Su, first author of the study and genetic epidemiologist, Institute of Prevention, Georgia School of Medicine, Augusta University
In this more objective assessment of movement-based sleep parameters, the researchers again found that, in general, night sleep decreases as our age increases, although they saw that the U-shape emerged in as sleep duration decreased significantly from 10 to 50 years and lengthened slightly thereafter. that. Studies of a large population of Japanese and French residents have shown a similar pattern.
The increase in sleep time later in life may reflect the fact that most Americans are still retiring at age 60 and simply do not need to get up so early. Health problems and not feeling well may be another reason why Americans sleep longer, researchers write, and more studies are needed to analyze these possible associations.
sleep efficiency -; basically the time you actually sleep versus the time you spent sleeping, with 85% considered good -; It also tends to decrease with age, although researchers found that it stabilized between the ages of 30 and 60, indicating that adults maintain sleep efficiency for a long time, but may sleep less in sleep. his busy middle age.
“Traditionally, people think that sleep efficiency decreases directly with age, but we found that there is a stable period, from 30 to 60 years, that you have a fairly stable sleep efficiency,” says Wang.
They found that women tend to sleep longer than men throughout their lives, but they tend to sleep later, especially as they get older, and get more interrupted, mostly to take care of children, but still sleep about four. minutes more than men.
The researchers were surprised to find that men and women were equally efficient at sleep, as women were more likely to report poorer sleep quality and more sleep disturbances. Although more studies are needed to understand sex differences in sleep, sex differences should already be taken into account in studies and treatment of sleep health, the researchers write. Women’s sleep start time is usually about five minutes later than men, but before the age of 20 men go to bed later.
Young American adults in their 20s had the last CTSO, or time for sleep, which is considered the time when participants actually went to bed, and students secondary had the biggest differences between weekdays and weekends between the time they went to bed and woke up. These week / night differences only occurred in people of school and working age with children between 14 and 17 years of age who show the largest differences.
For school-age children, the CTSO was at 9.30pm, which was not surprising, but this time it came later in high school and peaked around the age of 21, when the time average was closer to 11:30 p.m., McCall says, adding that he thought it would be even later. Researchers point out that 25% of children between the ages of 6 and 13 had a CTSO around 11 p.m.
While there may be social reasons, such as social demands and the use of electronic media just before bedtime, these patterns may also reflect the biological changes that occur during adolescence, they write. But the collective impact can be fatigue, behavior problems, and less academic success, they write.
As they turn 20, many people move into working life and the CTSO begins to reverse, he says. ” You came to the years when you were raising children and working and then what about the time of retirement? Your whole schedule is starting to change, “McCall said, and the CTSO is coming back later.
The researchers found that black Americans used to have some of the most annoying sleep parameters, usually going to bed later, sleeping fewer hours, and less efficiently than other races, including Mexican-Americans.
In the first apparent report of this type, Mexican Americans had the earliest sleep onset and the longest sleep time, but they were not necessarily efficient dormitories. The findings point to the need for more research on sleep racial disparities that takes into account social and cultural factors as well as biological and genetic factors, the researchers say.
A recent editorial in the Sleep Research Society’s Sleep Advances journal on cardiovascular health disparities reports that sleep disorders and poor sleep are emerging as factors contributing to disparities in cardiovascular outcomes in black patients. For example, obstructive sleep apnea, which affects about 26% of adults between the ages of 30 and 70 and tends to be more severe in blacks, has been linked to an increased risk of high blood pressure. coronary artery disease, stroke, heart failure and other diseases. Researchers, including the first author of the MCG pulmonologist, Dr. William J. Healy hypothesizes that innovative approaches to addressing disparities in sleep care delivery will reduce both sleep health disparities and potentially cardiovascular disparities.
“One thing we can’t overestimate is the impact of sleep,” Wang points out. Without enough sleep, “you abuse your body,” he says, and your ability to adapt to less sleep decreases with age.
While sleep deprivation is a risk factor for a myriad of health problems, from obesity to diabetes and cardiovascular disease, it can also be an indicator of illness, says McCall, who says that how we sleep is as a “canary in a coal mine” and that sleep complaints can be an indication of mental or physical health problems.
“I think what these sleep parameters mean when it comes to people’s health is that if you’re a doctor or another provider and patients come in with some kind of complaint about their sleep, you have to interpret what you they say in the light of their stage in life and what their likely sleep patterns will be, “says McCall.
For example, with a 22-year-old complaining of insomnia, some of his first questions would be what time you go to bed and how long it took you to fall asleep.
“I don’t necessarily look at our findings as a perfect health benchmark,” McCall says. “I see this as a benchmark for what’s happening in America.”
Our most natural instincts throughout our lives are probably going to sleep when it gets dark and waking up in the light, but life and obligations interfere with tracking the most natural 24-hour cycle of our internal circadian clocks. , say researchers.
Babies’ sleep patterns tend to follow these more natural circadian rhythms, Su points out. On frontier days, before television, the Internet, and cell phones, most of us probably sleep like babies, McCall says.
“Is it in the biology of a 20-year-old to always go to bed late or is it because they have friends they’re engaged to and have parties and college nights? I think there’s a lot of social influence here.” , says McCall. “Life stands in the way.”
Source:
Georgia School of Medicine, Augusta University
Magazine reference:
Su, S., et al. (2022) Epidemiology of accelerometer-based sleep parameters in U.S. school-age children and adults: NHANES 2011-2014. Scientific reports. doi.org/10.1038/s41598-022-11848-8