Community Neutrophil-to-Lymphocyte Ratio Can Predict Future Cardiovascular and Cardiac-related Mortality after the First Hospitalized COPD Exacerbation

Background: Patients with chronic obstructive pulmonary disease (COPD) have an increased risk of cardiovascular events, especially following acute exacerbation (AECOPD). However, there is insufficient data to identify high-risk sub-jects. Objectives: To evaluate the association between neutro-phil-to-lymphocyte ratio (NLR), a marker of inflammation, and the risk of cardiovascular events following exacerbation. Methods: This retrospective cohort included patients with COPD who were hospitalized with AECOPD between January 2016 and December 2022. We took the reference NLR before index admission and evaluated the incidence of major ad-verse cardiovascular events (MACE) or cardiovascular death over the following year. Multivariate analysis and competing risk regression were used to assess hazard ratio (HR) and NLR threshold for increased cardiovascular risk. Results: In total, 15,224 patients with AECOPD complet-ed one 1-year follow-up session. The majority were male (54%) with a mean age of 69 ± 3 years. The risk for MACE of patients in the highest NLR quartile was higher over the first year following AECOPD; however, the magnitude of effect decreased over time. After adjustment to other con-founders that may increase NLR, a value > 3.5 was found with the strongest predictive power Conclusion: Community NLR can be used to identify patients at increased risk of cardiovascular events following AECOPD, together with other risk factors. Every effort should be made to reduce exacerbation risk, and target in-tervention to those patients at highest risk.