TY - JOUR T1 - Neutrophil-to-lymphocyte ratio, blood eosinophils and COPD exacerbations: a cohort study JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.00471-2021 SP - 00471-2021 AU - Jens Ellingsen AU - Christer Janson AU - Kristina Bröms AU - Karin Lisspers AU - Björn Ställberg AU - Marieann Högman AU - Andrei Malinovschi Y1 - 2021/01/01 UR - http://openres.ersjournals.com/content/early/2021/10/28/23120541.00471-2021.abstract N2 - Background Blood neutrophil-to-lymphocyte ratio (NLR) and blood eosinophils (B-Eos) are emerging biomarkers in COPD. This study examined if they can predict acute exacerbations (AECOPD), and determined their longitudinal stability.Methods In this closed cohort study, Swedish subjects with spirometry-verified COPD attended three yearly visits in a stable phase of the disease. Blood cell counts, spirometry and questionnaire-assessed AECOPD history (worsening of COPD leading to an unscheduled visit and/or use of antibiotics and/or oral corticosteroids) were collected at each visit.Results Of 466 included subjects 57% were female. Baseline mean±sd forced expiratory volume in 1 s was 58±17% predicted. High NLR (≥3.0) was more common in subjects with previous AECOPDs than in those without (33.5% versus 20.4%, p=0.002). In two-level mixed-effects logistic regression models adjusted for confounders, NLR as a continuous variable (odds ratio, OR 1.20, 95% CI 1.04–1.38) and B-Eos ≥300 cells·µL−1 (OR 1.54, 95% CI 1.06–2.24) were associated with future AECOPDs. In 386 subjects with blood cell data available at all three visits, the intra-class correlation coefficient for NLR was 0.61 (95% CI 0.56–0.66) and for B-Eos 0.69 (95% CI 0.64–0.73). NLR was persistently ≥3.0 in 15.3% and B-Eos was persistently ≥300 cells·µL−1 in 10.6%.Conclusions Stable-phase NLR and B-Eos were associated with future AECOPDs. NLR on its own is probably not useful to predict AECOPDs, but might be included in a risk-scoring index. A minority of subjects with COPD had persistently elevated stable-phase NLR or B-Eos, and the biomarkers showed fair longitudinal reliability.FootnotesThis manuscript has recently been accepted for publication in the ERJ Open Research. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJOR online. Please open or download the PDF to view this article.Conflict of interest: Dr. Ellingsen reports personal fees from AstraZeneca, personal fees from GlaxoSmithKline, personal fees from Novartis, personal fees from TEVA, grants from Bror Hjerpstedt foundation, grants from Uppsala County Association against Heart and Lung Diseases, outside the submitted work.Conflict of interest: Dr. Janson has nothing to disclose.Conflict of interest: Dr. Bröms has nothing to disclose.Conflict of interest: Dr. Lisspers reports personal fees from AstraZeneca, personal fees from Novartis, personal fees from BoehringerIngelheim, personal fees from TEVA, personal fees from AstraZeneca, personal fees from GlaxoSmithKline, personal fees from BoehringerIngelheim, outside the submitted work; .Conflict of interest: Dr. Ställberg reports personal fees from AstraZeneca, personal fees from Novartis, personal fees from Boehringer Ingelheim, personal fees from Meda/Mylan, personal fees from TEVA, personal fees from GlaxoSmithKleine, personal fees from Chiesi, outside the submitted work; .Conflict of interest: Dr. Högman has nothing to disclose.Conflict of interest: Dr. Malinovschi has nothing to disclose. ER -