The role of neutrophil-lymphocyte ratio and platelet-lymphocyte ratio in exacerbation of chronic obstructive pulmonary disease

Objective: To investigate whether neutrophil-lymphocyte ratio and platelet-lymphocyte ratio like C-reactive protein can be used as markers of acute exacerbation in chronic obstructive pulmonary disease. Methods: The cross-sectional study was conducted at Konya Training and Research Hospital, Konya, Turkey, between December 2012 and April 2013, and comprised patients with stable and acute chronic obstructive pulmonary disease. All participants were male and aged >= 40 years. Patients were included prospectively from outpatient and emergency units according to recent Initiative for Chronic Obstructive Lung Disease 2013 criteria. C-reactive protein, neutrophil-lymphocyte ratio and platelet-lymphocyte ratio of each group were measured and compared. Results: Of the 94 patients, 48(51%) had stable disease with a mean age of 66.65+/-10.17 years (range: 49-79 years), and 46(49%) had acute exacerbation with a mean age of 62.67+/-9.41 years (range: 48-92 years). Mean levels of C-reactive protein, neutrophil-lymphocyte ratio and platelet-lymphocyte ratio were 5.04+/-6.65, 2.75+/-1.11 and 137.39+/-65.42 for stable disease, and 57.68+/-58.49, 7.99+/-5.72 and 231.18+/-141.36 for those with acute exacerbation (p=0.001). Cut-off values were neutrophil-lymphocyte ratio =3.3, platelet-lymphocyte ratio =150, and C-reactive protein =5 mg/dl. Positive predictive values for C-reactive protein, neutrophil-lymphocyte ratio and platelet-lymphocyte ratio were determined as 82% (odds ratio: 27.4); 85% (odds ratio: 32.5); and 73% (odds ratio: 6.3). Receiver-operating characteristic curve showed a significantly more area under curve of neutrophil-lymphocyte ratio (0.88) compared to platelet-lymphocyte ratio (0.74) (p<0.05). Conclusion: During acute exacerbations of chronic obstructive pulmonary disease, neutrophil-lymphocyte ratio may be used as an easily measurable, available and cost-effective parameter with high prognostic accuracy in clinical practice.