Increased in-hospital mortality and readmission risk associated with cardiovascular and cerebrovascular comorbidities in acute exacerbation of COPD patients

Cardiovascular and cerebrovascular comorbidities are prevalent in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD), but their impact on in-hospital outcomes and the risk of readmission remains unclear. This study aimed to describe the proportions of these comorbidities and assess their influence on patient outcomes. Hospital admission records from 2013 to 2020 with a primary discharge diagnosis of AECOPD were retrieved from Beijing Public Health Information Centre database. Comorbidities were identified through discharge diagnoses, while in-hospital outcomes and subsequent readmissions were tracked. Logistic regression model, generalised linear model and subdistributional hazard model were used to evaluate the associations between comorbidities and adverse outcomes. Among 98 127 patients, cardiovascular comorbidities were present in 78.3% of cases and cerebrovascular comorbidities were present in 30.3% of cases. Patients with cardiovascular comorbidities or cerebrovascular comorbidities or both had prolonged length of stay (ORs: 1.29, 95% CI: 1.23 to 1.35; 1.20, 95% CI: 1.10 to 1.32; 1.52, 95% CI: 1.44 to 1.60) and higher in-hospital mortality (ORs: 1.39, 95% CI: 1.19 to 1.62; 1.34, 95% CI: 1.04 to 1.75; 1.25, 95% CI: 1.06 to 1.48) compared with those without these conditions. Patients with cardiovascular comorbidities and those with both cardiovascular and cerebrovascular comorbidities were at increased risk of readmission (HRs: 1.14, 95% CI: 1.10 to 1.19; 1.19, 95% CI: 1.14 to 1.25), whereas cerebrovascular comorbidities alone were not. The impact of individual comorbidity varied, with heart failure, ischaemic heart disease, arrhythmia, hypertension, ischaemic stroke and cerebrovascular sequelae showing positive associations with adverse outcomes, but the opposite was observed for peripheral arterial disease, arterial stenosis and other cerebrovascular diseases. Most cardiovascular comorbidities and major cerebrovascular comorbidities are significant predictors of length of stay, in-hospital mortality and readmission in AECOPD patients. These findings highlight the need for targeted management strategies to improve outcomes in this high-risk population. Further research is needed to explore the mechanisms underlying these associations.