The impact of asthma on in-hospital outcomes of COVID-19 patients

Objective The impact of asthma as a possible risk factor for adverse clinical outcomes in patients diagnosed with COVID-19 remains controversial. The purpose of this study was to examine the impact of asthma on adverse clinical outcomes in a COVID-19 hospitalized cohort. Methods Retrospective, propensity-matched observational study of consecutive COVID-19-positive patients between February 24, 2020, and November 3, 2020 at a single health care system. Results In the initial population of 1925 patients, 4.4% presented with asthma. Propensity score matching reduced the total sample to n = 1045: 88 (8.4%) with asthma and n = 957 without asthma. A total of 164 (15.7%) patients died during the hospitalization, including 7 (8.0%) in the asthma group and 157 (16.4%), p = .037, in the non-asthmatic cohort. There was no difference between these groups in need for mechanical ventilation, length of stay on a ventilator, or hospital length of stay. Logistic regression analysis demonstrated that asthma was an independent predictor of lower mortality, while older age, BMI > 30 kg/m(2), heart failure, chronic kidney disease, and admission National Early Warning Score (NEWS) were significantly associated with an increased risk of in-hospital death. There were no significant differences between asthmatic and non-asthmatic cohorts with respect to need for mechanical ventilation, length of mechanical ventilation, serum markers of severe COVID-19 disease, or overall length of hospital stay. Conclusion We conclude that asthma in hospitalized COVID-19 patients is associated with a lower risk of mortality and no increase in disease severity in hospitalized COVID-19 patients.