Impact of coronavirus disease-2019 on chronic respiratory disease in South Korea: an NHIS COVID-19 database cohort study

BACKGROUND: The impact of underlying chronic respiratory diseases (CRDs) on the risk and mortality of patients with coronavirus disease 2019 (COVID-19) remains controversial. We aimed to investigate the effects of CRDs on the risk of COVID-19 and mortality among the population in South Korea. METHODS: The NHIS-COVID-19 database in South Korea was used for data extraction for this population-based cohort study. Chronic obstructive pulmonary disease (COPD), asthma, interstitial lung disease (ILD), lung cancer, lung disease due to external agents, obstructive sleep apnea (OSA), and tuberculosis of the lungs (TB) were considered CRDs. The primary endpoint was a diagnosis of COVID-19 between January 1st and June 4th, 2020; the secondary endpoint was hospital mortality of patients with COVID-19. Multivariable logistic regression modeling was used for statistical analysis. RESULTS: The final analysis included 122,040 individuals, 7669 (6.3%) were confirmed as COVID-19 until 4 June 2020, and 251 patients with COVID-19 (3.2%) passed away during hospitalization. Among total 122,040 individuals, 36,365 individuals were diagnosed with CRD between 2015 and 2019: COPD (4488, 3.6%), asthma (33,858, 27.2%), ILD (421, 0.3%), lung cancer (769, 0.6%), lung disease due to external agents (437, 0.4%), OSA (550, 0.4%), and TB (608, 0.5%). Among the CRDs, patients either with ILD or OSA had 1.63-fold (odds ratio [OR] 1.63, 95% confidence interval [CI] 1.17–2.26; P = 0.004) and 1.65-fold higher (OR 1.65, 95% CI 1.23–2.16; P < 0.001) incidence of COVID-19. In addition, among patients with COVID-19, the individuals with COPD and lung disease due to external agents had 1.56-fold (OR 1.56, 95% CI 1.06–2.2; P = 0.024) and 3.54-fold (OR 3.54, 95% CI 1.70–7.38; P < 0.001) higher risk of hospital mortality. CONCLUSIONS: Patients with OSA and ILD might have an increased risk of COVID-19. In addition, COPD and chronic lung disease due to external agents might be associated with a higher risk of mortality among patients with COVID-19. Our results suggest that prevention and management strategies should be carefully performed.