Risk of acute exacerbation of chronic obstructive pulmonary disease after COVID-19 recovery: a nationwide population-based cohort study

BackgroundChronic obstructive pulmonary disease (COPD) is associated with severe Coronavirus disease 2019 (COVID-19) outcomes. However, it is uncertain whether the risk of acute exacerbation of COPD (AECOPD) increases after recovering from COVID-19.MethodsThis study included 2,118 individuals with COPD from the Korea National Health Insurance Service database who were also diagnosed with COVID-19. Matched controls were chosen using 1:1 propensity score (PS) matching. We compared the risk of AECOPD after COVID-19 recovery between the COVID-19 cohort and matched controls between October 8, 2020, and December 31, 2021, using PS-matched Cox proportional hazard regression models.ResultsDuring a median follow-up of 62 days (interquartile range, 29-179 days), including a median of 14 days of recovery time after COVID-19, 68 people (5.6%) in the COVID-19 cohort and 50 (3.9%) in the matched control group experienced AECOPD. Compared to the matched controls, the COVID-19 cohort had a significantly higher risk of overall AECOPD (hazard ratio [HR] = 1.45, 95% confidence interval [CI] = 1.09-1.92). This increased risk was particularly evident for severe AECOPD among individuals who had severe COVID-19 within the first 30days post-recovery (aHR = 8.14, 95% CI = 3.32-19.97). When classified by COVID-19 severity, while severe COVID-19 significantly increased this risk (aHR = 2.97, 95% CI = 2.15-4.11), non-severe COVID did not significantly influence the risk of AECOPD, regardless of time duration or exacerbation severity.ConclusionIndividuals with COPD who had severe COVID-19 have increased risk of AECOPD after COVID-19 recovery, especially within the first 30 days after COVID-19 recovery.