Association between undiagnosed obstructive sleep apnea and severe course of COVID-19: a prospective observational study

PurposeObstructive sleep apnea (OSA) is associated with many long-term health consequences. We hypothesized that previously unrecognized and untreated OSA may be associated with more severe respiratory failure in hospitalized patients with COVID-19.MethodsPatients hospitalized in the Pulmonology Department with confirmed COVID-19, University Hospital in Krakow, Poland, between September 2020 and April 2021 were enrolled. OSA screening questionnaires including Epworth Sleepiness Scale (ESS), STOP-BANG, Berlin questionaire (BQ), OSA-50, and No-SAS were completed. Polygraphy was performed after > 24 h without requirement for supplemental oxygen.ResultsOf 125 patients with median age of 61.0 years, 71% of whom were male. OSA was diagnosed in 103 patients (82%) and was categorized as mild, moderate, and severe in 41 (33%), 30 (24%), and 32 (26%), respectively. Advanced respiratory support was introduced in 85 patients (68%), and 8 (7%) patients eventually required intubation. Multivariable analysis revealed that increased risk of requirement for advanced respiratory support was associated with higher respiratory event index (OR 1.03, 95%CI 1.00 to 1.07), oxygen desaturation index (OR 1.05, 95%CI 1.02 to 1.10), and hypoxic burden (1.02 95% CI 1.00 to 1.03) and lower minimal SpO(2) (OR 0.89, 95%CI 0.81 to 0.98), but not with results of OSA screening tools like BQ score (OR 0.66, 95%CI 0.38 to 1.16), STOP-BANG score (OR 0.73, 95%CI 0.51 to 1.01), NoSAS score (OR 1.01, 95%CI 0.87 to 1.18), or OSA50 score (OR 0.84, 95%CI 0.70 to 1.01).ConclusionPreviously undiagnosed OSA was common among hospitalized patients who survived the acute phase of COVID-19. The degree of OSA was associated with the severity of respiratory failure.