Abstract
Blood eosinophil count in chronic obstructive pulmonary disease (COPD) is associated with higher exacerbation rate and favourable response to corticosteroids; however, frequent exacerbations and use of inhaled corticosteroids could elevate pneumonia risk. We tested the hypothesis that high blood eosinophil counts are associated with high risk of pneumonia in individuals with severe COPD from the general population.
We included 7180 individuals with COPD from the Copenhagen General Population Study, including 643 with forced expiratory volume in 1 s (FEV1) <50% predicted between 2003 and 2011. All primary discharge diagnoses of pneumonia during follow-up were recorded.
Among individuals with COPD and FEV1 <50% pred, the multivariable adjusted incidence rate ratio was 2.17 (95% CI 1.31–3.58) for pneumonia comparing individuals with blood eosinophil counts ≥0.34×109 cells·L−1 versus <0.34×109 cells·L−1. In individuals with clinical COPD, defined by recent exacerbation, ≥10 pack-years of smoking and FEV1 <70% pred, the corresponding risk was 4.52 (2.11–9.72). Risk of pneumonia did not differ by blood eosinophil count in individuals with COPD and FEV1 ≥50% pred.
In individuals with COPD and FEV1 <50% pred, blood eosinophil count ≥0.34×109 cells·L−1 was associated with high risk of hospitalisation due to pneumonia.
Abstract
Eosinophilic COPD with severely impaired lung function is associated with high risk of pneumonia hospitalisations http://ow.ly/Tyl130jsi1D
Footnotes
This article has supplementary material available from erj.ersjournals.com
Conflict of interest: J. Vestbo has received personal fees from AstraZeneca, Boehringer Ingelheim, Chiesi Pharmaceuticals, GlaxoSmithKline and Novartis, outside the submitted work.
Conflict of interest: P. Lange has received grants and personal fees from Almirall, AstraZeneca, Boehringer Ingelheim, Novartis and GlaxoSmithKline, and personal fees from Norpharma, Takeda and Pfizer, outside the submitted work.
Support statement: The study was funded by the Lundbeck Foundation, Denmark, and the Faculty of Health and Medical Sciences, University of Copenhagen, Denmark. The sponsors of the study had no role in study design, data collection, data analysis, data interpretation or writing of the paper. Funding information for this article has been deposited with the Crossref Funder Registry.
- Received January 19, 2018.
- Accepted April 4, 2018.
- Copyright ©ERS 2018