Scientists from the University of Wisconsin’s School of Medicine and Public Health, in Madison, Wisconsin have released the results of a long-term study looking at possible connections between the symptoms of asthma and the development of Obstructive Sleep Apnea (OSA) in adults. The study began in 1988, and the results were released in January of this year. From the beginning of the study, the team of researchers looked at over 500 randomly selected adults, ages 30 to 60 years old at the onset of the study, and followed them every four years until shortly before releasing their results. These results, they found, show that asthma is linked to sleep apnea risks being higher, especially as adults further age.

Of those chosen randomly for the study, 466 of them did not have adult asthma symptoms and 81 of them did. Each participant attended an in-laboratory overnight stay to study their sleep patterns, concluding with a questionnaire about their sleeping habits, daytime sleepiness, etc. roughly every four years. The rate of OSA in each grouping remained essentially constant within each four-year interval, as twenty-two of the eighty-one participants who suffered from asthma experienced incidents of Obstructive Sleep Apnea, which is twenty-seven percent of this group, while only seventy-five of the four hundred and sixty-six participants who did not suffer from asthma experienced incidents of Obstructive Sleep Apnea, which is roughly sixteen percent of the group. In the last four-year interval that the participants were studies, the rate of Obstructive Sleep Apnea incidents remained at twenty-seven percent for those with asthma, and only increased to seventeen percent for the group without asthma. The authors of this study wrote, “This study prospectively examined the relationship of asthma with OSA assessed with laboratory-based polysomnography and found that preexistent asthma was a risk factor for the development of clinically relevant OSA in adulthood over a 4-year period. Furthermore, the asthma-OSA association was significantly dose-dependent on duration of asthma.” These results showed the scientists that, indeed, asthma is linked to sleep apnea risks being higher than they normally would without asthma. They concluded, “Studies investigating the mechanisms underlying this association and the value of periodic OSA evaluation in patients with asthma are warranted,” adding that they would conduct further studies to find a direct causal relationship between asthma and the risks of Obstructive Sleep Apnea.