Scientists Explore Why Asthma Gets Worse at Night

Sep, 2021 - By SMI

Researchers studied the influence of circadian system, unveiling the important role of biological clock in asthma.

Many of the asthma patients suffer from flare-ups frequently at night and it’s often considered to be a result of environmental changes and behavioral factors. A research team at Brigham and Women’s Hospital and Oregon Health & Science University studied the influence of circadian system, revealing the key role of biological clock in asthma. The scientists claim that this is one of the first investigations to isolate the influence of the circadian system from other factors. Understanding the processes that worsens asthma could help study and treat the disease in an efficient way.

The scientists conducted two experiments on 17 people with asthma to isolate the circadian cycle effect on the illness. The experiments were named “constant routine” and “forced desynchrony” respectively. In the first experiments i.e. constant routine- patients were made to stay awake for 38 hours in constant dim light environments. The subjects were told to keep a fixed sitting position for the period of 38 hours and were provided with same caloric food every two hours to eliminate as many factors that affect asthma as much as possible. It allowed them to investigate the circadian rhythmicity on asthma symptoms. In “forced desynchrony” subjects were placed in seven day, 28 hour sleep/wake cycle with regular behavior evenly planned for 28 hour days. This experiment was carried out to separate the normal behaviors from internal 24-hour circadian systems.

Both the experiments showed that circadian rhythms have a key role in regulation of pulmonary function over a daily cycle. The second experiment showed that sleep stages act out a significant role in asthma severity free of circadian effects. However, circadian cycles and sleep/wake behavioral cycles affected asthma in same way. Therefore, according to the scientists, the ultimate cause of asthma worsening at night is somewhat an even blend of behaviors and circadian cycles.