Clinical utility of blood neutrophil-lymphocyte ratio in Japanese COPD patients

摘要

Neutrophil-to-lymphocyte ratio (NLR) is a biomarker of inflammation in chronic obstructive pulmonary disease (COPD) patients. But, a meaningful threshold and the longitudinal changes are unknown. We aimed to investigate the association between NLR and the clinical characteristics of COPD patients and to determine a meaningful threshold and the longitudinal changes for NLR. Keio University and its affiliate hospitals conducted an observational COPD cohort study over 3?years. We performed a blood examination and a pulmonary function test. Blood examination was completed at baseline and annually thereafter, at a time when the disease was stable. Two hundred seventy-four patients who had at least 3 blood examinations over 3?years were included. Baseline NLR was correlated with baseline C-reactive protein (CRP) (r?=?0.18, p?=?0.003) and SAA (r?=?0.34, p?< 0.001). We defined an NLR score of 2.7 as the arbitrary cut-off value based on upper quartile points. COPD patients with NLR?≥?2.7 were older (p?=?0.037), had a lower BMI (p?=?0.005) and a lower %FEV1 (p?=?0.0003) compared to patients with NLR?