Neutrophil-lymphocyte ratio as a marker of disease severity and exacerbation in COPD

INTRODUCTION: Since the burden of COPD is increasing day by day and is a leading cause of mortality, it is important to have a prognostic marker for COPD. The well-known prognostic marker for COPD is the BODE score which includes 1) BMI 2) Degree OF Obstruction 3) Dyspnoea Scale 4) Exercise Capacity. Since the calculation Of BODE score is cumbersome and is not possible in sick patients, it is important to have a simple prognostic marker like Neutrophil- Lymphocyte Ratio(NLR) which can be easily obtained from a routine complete blood count which correlates well with that of BODE score. AIMS AND OBJECTIVES: 1.To assess whether Neutrophil-to-Lymphocyte ratio can be used to assess the severity of disease by comparing it with BODE score in COPD 2. To assess whether the Neutrophil Lymphocyte ratio is higher in COPD exacerbation compared to patients with stable COPD MATERIALS & METHODS: This analytical cross-sectional study is to be conducted among 80 patients which includes 30 patients who attend the emergency department of Gov.Rajaji Hospital, Madurai in a state of COPD Acute exacerbation and 50 Stable COPD patients who attend the OPD for followup. METHODOLOGY: A detailed history including duration of illness, smoking history, packyears and any past medical history was taken. Degree of dyspnoea was assessed using Modified Medical Research Council (MMRC) dyspnoea scale. Body mass index(BMI) calculated. Pulmonary function tests were done including FEV1/FVC and Post-bronchodilator FEV1.Peripheral blood samples were collected from all patients within 24hours of admission which includes total count, differential count of neutrophils and lymphocytes. Neutrophil-tolymphocyte ratio was calculated by dividing absolute neutrophil count by absolute lymphocyte count .BODE score was calculated in the stable COPD group. RESULTS: COPD is more prevalent among smokers and male sex.Low BMI is a risk factor for severe disease.NLR correlated with the severity of airflow obstruction.NLR has a positive correlation with mMRC scale. NLR correlated inversely with 6-minute walk distance. Thus,NLR correlated inversely with BMI,FEV1%,6-minute walk distance and has a positive correlation with mMRC scale. NLR correlated with the disease severity as it has positive correlation with BODE score. NLR was significantly higher in COPD exacerbation compared to patients with stable COPD CONCLUSION: NLR correlates well with the disease severity in stable COPD as compared to BODE score. So, it should be used as a routine prognostic marker of mortality in all patients with COPD.NLR can be used as a marker of COPD exacerbations