Neutrophil to lymphocyte ratio and platelet to lymphocyte ratio in patients with acute exacerbation of chronic obstructive pulmonary disease

Abstract

Introduction: The platelet to lymphocyte ratio (PLR) and neutrophil to lymphocyte ratio (NLR) are markers of inflammation that have been reported to be elevated in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) compared to stable state. The aim of this study was to determine the association between these parameters and the severity and outcomes of AECOPD. Patients and Methods: We conducted a retrospective study of patients admitted with a diagnosis of AECOPD between January 2014 and December 2017. Clinical characteristics, NLR, PLR, and serum levels of C-reactive protein (CRP) and other data on admission were recorded. Results: A total of 100 patients (91% male; average age 66.89years±11.05 were included in the study. COPD was severe (GOLD C and D) in 57% of cases. The mean level of NLR and PLR were respectively 7.66+/-8.62 and 33.57+/-23.32. NLR and PLR correlated with serum CRP level (r=0.658; p=0.02). Negative and statistically significant correlation was found between NLR and VEMS/CVF (r=0.632; p=0.007). NLR was significantly associated to hypercapnia level (r=0.568; p=0.04) and arterial oxygen saturation (r=0.568; p=0.05). Otherwise, PLR was higher among patients with acidosis (p=0.005) and desaturation (p=0.01) and was associated to longer hospitalization duration (p=0.02). Patients who needed non invasive ventilation, mechanic ventilation or died had higher NLR and PLR levels (p>0.05). Conclusion: NLR and PLR were increased in severe AECOPD and were associated with poor prognosis.