Prognostic Value of Neutrophil-to-Lymphocyte Ratio in COPD for Predicting Exacerbation and Mortality Outcomes

Manimekalai P ¹, Suresh Kanna S ¹, Vijaykumar Edward ¹ Anandan P ^1*

This meta-analysis clarifies NLR's prognostic role in COPD, revealing its potential as a predictive marker for exacerbation and mortality.

Abstract

Background: Aging is a significant risk factor for chronic diseases, including chronic obstructive pulmonary disease (COPD). COPD patients are known to develop more comorbidities than non-COPD individuals. This study hypothesizes that comorbidities typically associated with aging manifest earlier in COPD patients. Methods: A meta-analysis was conducted following PRISMA guidelines. A systematic search was performed in databases like PubMed, EMBASE, and Cochrane Central Register, focusing on the association between neutrophil-to-lymphocyte ratio (NLR) and COPD outcomes. Studies were selected based on defined inclusion criteria, and data extraction was done independently by two reviewers. The pooled odds ratios (ORs) were calculated using a random-effects model, and heterogeneity was assessed using the I² statistic. Results: Nine studies with a total of 5,140 COPD patients were included. The meta-analysis found that a higher NLR is significantly associated with an increased risk of COPD exacerbation and mortality. Subgroup analysis revealed that this association was particularly strong in older patients and those of Asian descent. The study also noted considerable heterogeneity, particularly related to the impact of glucocorticoid treatment. Conclusion: NLR is a valuable prognostic biomarker in COPD, predicting both exacerbation and mortality. Its use in clinical practice could enhance patient risk stratification, especially in older populations. Further research is needed to explore the underlying mechanisms and potential for targeted interventions based on NLR levels.

Keywords: Chronic obstructive pulmonary disease (COPD), Neutrophil-to-lymphocyte ratio (NLR), Inflammation biomarkers, COPD exacerbation, Mortality prediction

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