Predictive factors for obstructive sleep apnea in adults with severe asthma receiving biologics: a single-center cross-sectional study

Abstract

Purpose: To evaluate the prevalence and potential predictors of obstructive sleep apnea (OSA) in a cohort of adults with severe asthma.

Methods: From March 2021 to December 2021, this cross-sectional study enrolled patients with severe asthma receiving biologics, who were consecutively referred for sleep evaluation irrespective of sleep-related symptoms. Clinical and functional data, including three OSA screening instruments (GOAL, STOP-Bang, and NoSAS) were recorded. All participants underwent a portable sleep test (ApneaLink Air™). OSA diagnosis was based on the respiratory disturbance index ≥ 5.0/h and subclassified according to severity thresholds. Data were subjected to logistic regression tests to identify possible predictors for OSA. Discrimination was estimated from the area under the curve (AUC).

Results: Overall, 56 outpatients were included (80% females): 54% with any OSA, 13% with moderate-to-severe OSA, and 4% with severe OSA. In the multivariate analysis, no parameter emerged as an independent predictor for OSA: age (p = 0.080), body mass index (p = 0.060), loud snoring (p = 0.130), and hypertension (p = 0.848). No screening instrument was useful to predict any OSA: GOAL (AUC: 0.714; 95% confidence interval (CI): 0.579-0.849), NoSAS (AUC: 0.645; 95% CI: 0.497-0.793), and STOP-Bang (AUC: 0.640; 95% CI: 0.493-0.788). Similarly, no screening tool was also useful for predicting moderate-to-severe OSA or severe OSA.

Conclusion: Patients with evere asthma receiving biologics exhibit a high prevalence of OSA. However, no clinical, functional, or OSA screening instrument showed acceptable discriminatory ability to predict the presence of OSA in these patients with severe asthma.

Keywords: Asthma; Clinical predictors; Diagnosis; Obstructive sleep apnea; Screening.