PT  - JOURNAL ARTICLE
AU  - Wan C. Tan
AU  - Jean Bourbeau
AU  - Gilbert Nadeau
AU  - Wendy Wang
AU  - Neil Barnes
AU  - Sarah H. Landis
AU  - Miranda Kirby
AU  - James C. Hogg
AU  - Don D. Sin
ED  - ,
TI  - High eosinophil counts predict decline in FEV<sub>1</sub>: results from the CanCOLD study
AID  - 10.1183/13993003.00838-2020
DP  - 2021 May 01
TA  - European Respiratory Journal
PG  - 2000838
VI  - 57
IP  - 5
4099  - http://erj.ersjournals.com/content/57/5/2000838.short
4100  - http://erj.ersjournals.com/content/57/5/2000838.full
SO  - Eur Respir J2021 May 01; 57
AB  - Introduction The aim of this study was to examine the association between blood eosinophil levels and the decline in lung function in individuals aged >40 years from the general population.Methods The study evaluated the eosinophil counts from thawed blood in 1120 participants (mean age 65 years) from the prospective population-based Canadian Cohort of Obstructive Lung Disease (CanCOLD) study. Participants answered interviewer-administered respiratory questionnaires and performed pre-/post-bronchodilator spirometric tests at 18-month intervals; computed tomography (CT) imaging was performed at baseline. Statistical analyses to describe the relationship between eosinophil levels and decline in forced expiratory volume in 1 s (FEV1) were performed using random mixed-effects regression models with adjustments for demographics, smoking, baseline FEV1, ever-asthma and history of exacerbations in the previous 12 months. CT measurements were compared between eosinophil subgroups using ANOVA.Results Participants who had a peripheral eosinophil count of ≥300 cells·µL−1 (n=273) had a greater decline in FEV1 compared with those with eosinophil counts of <150 cells·µL−1 (n=430; p=0.003) (reference group) and 150–<300 cells·µL−1 (n=417; p=0.003). The absolute change in FEV1 was −32.99 mL·year−1 for participants with eosinophil counts <150 cells·µL−1; −38.78 mL·year−1 for those with 150–<300 cells·µL−1 and −67.30 mL·year−1 for participants with ≥300 cells·µL−1. In COPD, higher eosinophil count was associated with quantitative CT measurements reflecting both small and large airway abnormalities.Conclusion A blood eosinophil count of ≥300 cells·µL−1 is an independent risk factor for accelerated lung function decline in older adults and is related to undetected structural airway abnormalities.This study shows that high blood eosinophil count is significantly related to rapid FEV1 decline in all people, independent of well-established risk factors such as smoking and age, and may be related to undetected airway abnormalities https://bit.ly/36o8Cc6