Risk of Stroke in COVID-19 Survivors With Asthma: A Nationwide, Population-Based Cohort Study

Background: The impact of coronavirus disease 2019 (COVID-19) on stroke risk in adult individuals with asthma post-recovery remains unclear. Methods: Using a longitudinal retrospective cohort design based on the Korean National Health Insurance Service claims database, we analyzed stroke risk in two parts. Study 1 examined stroke risk in individuals with asthma according to COVID-19 severity, and Study 2 compared stroke risk between individuals with asthma (asthma cohort) and the general population without asthma (general population cohort), considering COVID-19 severity. Both studies used propensity score matching and Cox proportional hazards regression models for risk estimation. Results: In Study 1, which evaluated stroke risk in the asthma cohort, the risk of stroke was significantly higher in the asthma cohort with severe COVID-19 compared to the asthma cohort without COVID-19 (adjusted hazard ratio [aHR], 1.88; 95% confidence interval [CI], 1.02–3.46). In Study 2, which evaluated stroke risk across six groups stratified by asthma status (asthma cohort and general population cohort) and COVID-19 severity (no, non-severe, and severe COVID-19), stroke risk was highest in the asthma cohort with severe COVID-19 (aHR, 3.42; 95% CI, 1.72–6.79, referring to the general population group without COVID-19), suggesting that severe COVID-19 has a more substantial effect on stroke risk in individuals with asthma. Conclusion: This study highlights a significant association between severe COVID-19 and stroke occurrence in adults with asthma, emphasizing the need for ongoing stroke monitoring to improve long-term asthma outcomes during the COVID-19 endemic period.