(RxWiki News) It's a twist on the classic puzzle about the chicken and the egg. Which comes first — asthma or sleep apnea?
A new study found that people with asthma were more likely to develop obstructive sleep apnea. The longer someone had asthma — a chronic illness that causes swelling and narrowing of the airways — the more likely they were to get obstructive sleep apnea, they found.
“It is important for clinicians treating asthma to have a greater concern for the potential of obstructive sleep apnea in their asthmatic patients,” said John Oppenheimer, MD, Fellow of the American Academy of Allergy, Asthma & Immunology, in an interview with dailyRx News.
This study took place between 1988 and 2013 in Wisconsin. Mihaela Teodorescu, MD, of the University of Wisconsin School of Public Health, and colleagues conducted this research. Over 500 adults from across the state had a sleep study and answered surveys about their health every four years.
Among these study patients, 81 had asthma. None had sleep apnea at the start of this study. In the first four years of follow-up, 22 of the 81 people with diagnosed asthma — or 27 percent — developed obstructive sleep apnea. Only 17 percent, or 75 of the 466 people without asthma, developed sleep apnea.
Obstructive sleep apnea is a condition in which people repeatedly stop breathing for several seconds as they sleep, which causes them to wake often, snore, and be tired during the day because their sleep was not restful.
In the entire study period, 56 percent of the patients with asthma developed sleep apnea — compared to 34 percent of those without asthma.
People who snore — a sign of sleep apnea — should talk to their doctor. There are many ways to help sleep apnea patients, such as fitting them with a mouth device called a continuous positive airway pressure (CPAP) machine that keeps the airway open while they sleep. Dr. Teodorescu and team noted that helping people overcome sleep apnea may improve their asthma symptoms, too.
It's hard to know whether asthma or obstructive sleep apnea is what causes fatigue during the day, Dr. Oppenheimer said.
“Interestingly, the inflammation of asthma peaks 2 to 4 in the AM," Dr. Oppenheimer said. "Thus, it is not uncommon for asthmatics to have nighttime awakening."
Because sleep apnea can also cause frequent waking as a person struggles for breath, "it makes the complaint of fatigue a real conundrum — is it asthma or sleep apnea?” Dr. Oppenheimer added.
Dr. Teodorescu and colleagues said it may be that having asthma makes patients more inclined to develop sleep apnea, but they noted that further studies are needed to confirm this.
This study was published Jan. 13 in JAMA.
Funding came from several sources, such as the National Heart, Lung, and Blood Institute and the National Institute on Aging. The authors disclosed no conflicts of interest.