Propensity Score Analysis of the Association between Chronic Obstructive Lung Disease and Stroke Outcome: Thailand's National Database

Introduction: The impact of coexisting chronic obstructive lung disease (COPD) in patients with stroke remains unclear. This study aims to investigate the effect of COPD on survival and hospital outcomes among stroke patients. Methods: The outcomes of patients with stroke between fiscal years 2005 and 2017 from Thailand's Universal Coverage Scheme database were compared between COPD and non-COPD patients using propensity score matching and flexible parametric survival model. Results: A total of 805,561 patients were admitted with stroke during the study period, 12,650 (1.92%) of whom had been diagnosed with COPD. Participants with COPD were significantly older, were more likely to be male, and had higher prevalences of pre-existing atrial fibrillation, ischemic heart disease, and heart failure and a higher incidence of ischemic stroke (p < 0.001). The propensity score-matched groups were well balanced in terms of all observed covariates. Participants with COPD had higher incidences of pneumonia (odds ratio [OR] 1.98, 95% confidence interval [CI]: 1.83-2.15), urinary tract infection (OR 1.27, 95% CI: 1.14-1.42), sepsis (OR 1.50, 95% CI: 1.32-1.70), cardiac arrest (OR 1.50, 95% CI: 1.19-1.88), respiratory failure (OR 1.82, 95% CI: 1.69-1.96), acute kidney injury (OR 1.29, 95% CI: 1.14-1.46), and in-hospital death (OR 1.21, 95% CI: 1.13-1.30) than those without. The impact of COPD on mortality was highest at day 93 (hazard ratio [HR] 1.73, 95% CI: 1.60-1.87) and nonsignificant at day 965 of follow-up (HR 1.08, 95% CI: 1.00-1.16). Conclusions: COPD was associated with respiratory, cardiac, renal, and infectious complications and significantly impacted survival for up to 2.6 years.