New York: Hundreds of years ago, people noticed that the severity of asthma got worse at night. The researchers identified the effect of the circadian system as the cause, not sleep and physical activities, as has been traditionally thought.
Up to 75 percent of people with asthma report having asthma exacerbations at night. Many behavioral and environmental factors, including exercise, air temperature, posture, and sleep environment, are known to influence asthma severity.
In the study, the team from Brigham and Women’s Hospital and Oregon Health & Science University wanted to understand the contributions of the internal circadian system to this problem.
The circadian system consists of a central pacemaker in the brain (the suprachiasmatic nucleus) and “clocks” throughout the body which is critical for coordinating bodily functions and for anticipating the environmental and behavioral requirements of daily cycling.
Frank A. J. L. Sher, MD, director of the Clinical Chronobiology Program in Brigham’s Division of Sleep and Circadian Disorders.
“We’ve observed that people with the worst asthma, in general, are the people who have the greatest decreases in lung function caused by the nighttime circadian clock, and also have the largest changes caused by behaviors, including sleep,” Stephen A. added. Shea, professor and director at the Oregon Institute of Occupational Health Sciences.
The results were published in The Proceedings of the National Academy of Sciences.
To understand the impact of the daily regimen, the team enrolled 17 asthmatic participants (who weren’t talking about steroid medications, but used their bronchodilator inhalers whenever they felt their asthma symptoms were getting worse) in two complementary lab protocols where lung function and asthma symptoms and dilator use were assessed. bronchi continuously.
In the “continuous routine” protocol, participants spent 38 hours continuously awake, in a stationary position, and under low light conditions, with identical snacks every two hours.
In a “compulsive desynchronization” protocol, participants were placed on a repetitive 28-h sleep/wake cycle for a week in low light conditions, with all behaviors evenly scheduled across the cycle.