COVID-19 susceptibility in bronchial asthma

Green, Ilan; Merzon, Eugene; Vinker, Shlomo; Golan-Cohen, Avivit; Magen, Eli

Background Bronchial asthma has not been adequately assessed in the coronavirus disease 2019 (COVID-19). Respiratory allergy is associated with significant reductions in ACE2 receptors expression, which is the entry receptor for COVID-19. Objective To observe COVID-19 susceptibility in patients with bronchial asthma, we have analyzed the prevalence of asthma in a large cohort of consecutive outpatient subjects who tested in the RT-PCR assay for COVID-19. Methods This was a retrospective population-based cross-sectional study utilizing data from a large nation-wide health maintenance organization (HMO) in Israel. All HMO enrollees who had been tested for COVID-19 from February to June 2020 were included. Differences in demographic and clinical characteristics between the subjects with negative and positive COVID-19 RT-PCR tests and between COVID-19 RT-PCR positive subjects with and without asthma were analyzed. Results A total of 37,469 subjects were tested for COVID-19 RT-PCR and 2,266 (6.05 %) of them were positive. A significantly higher proportion of smokers was observed in the COVID-19 negative group, than in the COVID-19 positive group (4,734 (13.45 %) vs 103 (4.55 %); p<0.001). Asthma was found in 153 (6.75 %) subjects of COVID-19 positive and in 3,388 (9.62 %) subjects of COVID-19 negative group (p<0.001). No significant impact of antileukotrienes, inhaled corticosteroids and long-acting beta-blockers use was revealed on COVID-19 positivity proportions. Multiple logistic regression analysis adjusted for sex, age, smoking, and comorbidity revealed a negative association of asthma with the likelihood of being positive for COVID-19 (OR 0.71 (95% confidence interval, 0.58-0.87); p=0.001). Conclusion we observed lower COVID-19 susceptibility in patients with pre-existing asthma.