Association of Inhaled Corticosteroid Use with COVID-19 Severity and Hospitalization in Patients With and Without Respiratory Disease

Background: Several studies have demonstrated the benefit of inhaled corticosteroids (ICS) before COVID-19 illness in reducing hospitalization time and reducing viral entrance to lung cells. This study explores the risk of severe COVID-19 illness among patients who had purchased ICS. Methods: In a retrospective study, adult patients with COVID-19 before the emergence of the Omicron variant were included. The severity, hospitalization rates, and mortality due to COVID-19 among patients who purchased and did not purchase ICS during the 6 months before the illness were compared. Results: Of the 44,866 COVID-19 patients, 2359 (5.3%) were hospitalized. Information regarding the severity of hospitalization was available for 2259 patients. Of these, 602 (27%) were classified as having severe disease and 510 (22%) died. Patients with higher socioeconomic status (SES) had less hospitalization rates but significantly higher risk for severe COVID-19 and a higher mortality rate. In a multivariate analysis, a significantly higher risk for hospitalization was found only for patients who purchased ICS when no respiratory disease was recorded (odds ratio 1.53,95% confidence interval: 1.15-2.01), relative to those who did not purchase ICS. Conclusions: Patients with unrecorded respiratory disease who purchased ICS are at higher risk for hospitalization due to COVID-19; therefore, rigorous attempts should be made to better characterize their illness. Higher SES was associated with more severe COVID-19 and higher mortality rates and these patients should have early hospitalization.