Sleep-disordered breathing (SDB), a common pediatric condition, is believed to be associated with another common condition in children—asthma. It is less clear how SDB is correlated with severe asthma. In a recent study, researchers investigated the prevalence of SDB in a pediatric severe asthma program and how SDB is related to asthma control and function. The results of the study were published online as part of the ATS 2020 International Conference.
The study took place at the Boston Children’s Hospital Pediatric Severe Asthma Program. Patients attending clinic visits completed the Pediatric Sleep Questionnaire (PSQ), Asthma Control Test (ACT), and spirometry. SDB was defined as PSQ score >0.33; the correlations between this score and ACT score and with spirometry values were observed. Researchers also assessed the role of age and sex.
Final analysis included 36 patients (mean age, 11.5 years; 61.1% were male) with 69 observations. Just under half of patients (n=15; 47.1%) had SDB; boys were more likely than girls to have SDB (50.0% vs. 28.6%). Among the observations, the median PSQ score was 0.23. The median ACT score was 19. Mean forced expiratory volume 1 (FEV1) percentage predicted was 97.2% predicted, and mean FEV1/forced vital capacity (FVC) was 82.0%.
PSQ score was moderately negatively correlated with ACT score (P<0.001). Patients with a positive PSQ had an average ACT score five points lower compared with those with a negative PSQ (P<0.0001). Using multivariable linear regression models, the researchers observed a significant sex interaction with PSQ on asthma control: In girls, for every 0.10-point increase in PSQ score, there was a 1.92 decrease in ACT score. In boys, the ACT score decreased by 0.76 points. Multivariable linear regression models also pointed to a notable age interaction with a positive PSQ screen on FEV1/FVC: Among children aged 5 to 12 years, a positive PSQ was correlated with a significantly lower FEV1/FVC; the effect gradually decreased as age increased, with the correlation no longer presenting in children aged 13 years and older.
“Our study suggests that SDB is highly prevalent among pediatric [patients with] severe asthma. These findings suggest a dynamic relationship between SDB and asthma control and lung function in these patients, where age and sex appear to play a significant role,” the study authors concluded.