Association of asthma comorbidity with poor prognosis of coronavirus disease 2019

Kim, Sae-Hoon; Ji, Eunjeong; Won, Seung-Hyun; Cho, Jungwon; Kim, Yong-Hyun; Ahn, Soyeon; Chang, Yoon-Seok

Background While global health agencies have listed asthma as a vulnerability for severe cases of coronavirus disease 2019 (COVID-19), the evidence supporting this is scarce. Methods A nationwide cohort study was conducted using the validated Korean national health insurance claim data of patients diagnosed with COVID-19 between January 1 and April 8, 2020. Asthma comorbidity was determined using a diagnosis code assigned by the physician and the prescription of asthma-related medications. The clinical course of COVID-19 was classified into three severity grades according to the requirements for oxygen supply and mechanical ventilation. We also evaluated the association of asthma with overall and in-hospital mortality of COVID-19. Results Asthma morbidity was a significant risk factor for severe COVID-19 (grade 2 requiring oxygen supply) (adjusted odds ratio [aOR]=1.341, 95% confidence interval [CI], 1.051−1.711, P=0.018) and grade 3 requiring mechanical ventilation or leading to death (aOR=1.723, 95% CI: 1.230−2.412, P=0.002) multinomial logistic regression adjusting co-risk factors. Asthma was also significantly associated with mortality of COVID-19 (aOR=1.453, 95% CI: 1.015−2.080, P=0.041) and was revealed to have a shorter time to in-hospital mortality of COVID-19 (P<0.001). Patients with recent asthma exacerbation showed more severe COVID-19 of grade 3 (OR=7.371, 95% CI: 2.018−26.924, P=0.003) and higher mortality (OR=9.208, 95% CI: 2.597−32.646, P<0.001) in univariable analysis, but the statistical significance was not found in multivariable analysis. Conclusion Asthma morbidity was associated with severity and mortality of COVID-19. Patients with asthma should pay more attention to avoid worsening of COVID-19.