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Bad sleep quality and quantity may put you at greater risk for developing asthma, according to a new study.
Previous research has already shown that asthma tends to lead to sleep issues, but researchers wanted to know if the association worked the other way — that is, whether how someone slept impacted their likelihood of developing asthma, said the study, which published Monday in the journal BMJ Open Respiratory Research.
“We’ve always known that there is some association between asthma and sleep but most of the work had been done on the presence of obstructive sleep apnea,” said pediatric allergist Dr. Amal Assa’ad, associate director of the Division of Allergy and Immunology at Cincinnati Children’s Hospital Medical Center. She was not involved in the latest study.
To investigate, researchers looked at the data of a cohort from 2006 to 2010 with more than 450,000 people in the UK Biobank, a large biomedical database and research resource that is following residents long-term. The people studied ranged in age from 38 to 73 years old, the report said.
At a 10-year follow-up, nearly 18,000 people in the research were diagnosed with asthma, according to the study. Analysis of the data showed that people with both a genetic predisposition and poor sleep habits were twice as likely to develop asthma than people in a low-risk group.
Typically, having a genetic predisposition puts you at a 25% to 30% greater risk of developing asthma, said Dr. Juanita Mora, a Chicago-based allergist/immunologist and national spokesperson for the American Lung Association. She was not involved in the research.
There is good news: Healthy sleep patterns were shown to be associated with lower risk of asthma no matter the genetic susceptibility, the study said.
People with high-risk genes and good sleep patterns had slightly lower risk of developing asthma than people who had a low genetic risk and bad sleep patterns, the authors added.
By monitoring and treating sleep conditions, health professionals might also be mitigating the development of asthma, the study authors wrote. If sleep traits were improved, 19% of asthma cases could be prevented, according to the research.
This finding also points to a greater need for doctors and nurses to talk to their patients with asthma about their sleep habits to see if their behavior is worsening symptoms, Mora added.
Better sleep is good for everyone
The key to understanding this study is understanding the interplay between genetics and behavior, Assa’ad said.
The researchers looked at all the small changes in DNA that can put someone at greater risk for developing asthma, she added. Those markers and the risk in the genetics become what’s called a person’s polygenic risk score.
But most people don’t know their genetic score for how susceptible they are to developing asthma and instead are only aware of how severe their symptoms are, Assa’ad said.
What people can do is track their trigger and exacerbating factors — of which sleep seems to be one of many — to get optimal control over their asthma, Mora said.
The results may underscore the importance of good sleep hygiene for everyone, regardless of their asthma genetics, she added.
Inflammation may be behind why sleep is so important to managing or preventing asthma, according to the study.
Asthma is generally considered a chronic inflammatory disease, the study said. Previous research has shown that problems with sleep duration and insomnia are associated with chronic inflammation.
Sleep disorders are also associated with chronic activation of the stress response, parts of which are key in the development of asthma, the study said.
Good sleep hygiene
Adults need at least seven hours of sleep a night, according to the US Centers for Disease Control and Prevention.
For many people, that isn’t happening — 1 in 3 Americans have a sleep deficit, according to the CDC.
But it’s not just quantity that you should focus on — quality matters, too.
“Signs of poor sleep quality include not feeling rested even after getting enough sleep, repeatedly waking up during the night, and experiencing symptoms of sleep disorders (such as snoring or gasping for air),” the CDC said.
That is where good sleep hygiene (or habits) come into play.
The CDC recommends going to bed and waking up at the same time consistently, keeping the bedroom comfortable and dark, and avoiding electronics before bed.
A comfortable room typically means one that is cool — about 60 to 67 degrees Fahrenheit (15 to 20 degrees Celsius), according to a 2021 CNN story.
A routine to get you ready for sleep isn’t just for kids who need a bath and book before bed. Winding down with familiar activities is a great way to signal to brains of all ages that it is time to rest, pediatric sleep expert Ariel Williamson, a psychologist at the Children’s Hospital of Philadelphia, told CNN earlier this year.
You should also avoid large meals, caffeine and alcohol too close to bedtime and get active during the day for better sleep.
If none of those changes improves your sleep, it may be time to see a doctor, experts say.