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Multicenter Study
. 2010 Jun 15;11(1):77.
doi: 10.1186/1465-9921-11-77.

Sputum neutrophils as a biomarker in COPD: findings from the ECLIPSE study

Dave Singh  1 , Lisa Edwards, Ruth Tal-Singer, Stephen Rennard
Affiliations
Multicenter Study

Sputum neutrophils as a biomarker in COPD: findings from the ECLIPSE study

Dave Singh et al. Respir Res. .

Abstract

Introduction: The percentage of neutrophils in sputum are increased in COPD patients, and may therefore be a biomarker of airway inflammation. We studied the relationships between sputum neutrophils and FEV1, health status, exacerbation rates, systemic inflammation and emphysema, and long term variability at 1 year.

Methods: Sputum samples were obtained from 488 COPD patients within the ECLIPSE cohort. 359 samples were obtained at baseline, and 297 after 1 year. 168 subjects provided samples at both visits. Serum interleukin-6 (IL-6), IL-8, surfactant protein D and C-reactive protein levels were measured by immunoassays. Low-dose CT scans evaluated emphysema.

Results: Sputum neutrophil % increased with GOLD stage. There was a weak association between % sputum neutrophils and FEV1 % predicted (univariate r2 = 0.025 and 0.094 at baseline and year 1 respectively, p < 0.05 after multivariate regression). Similar weak but significant associations were observed between neutrophil % and health status measured using the St Georges Respiratory Questionairre. There were no associations between neutrophils and exacerbation rates or emphysema. Associations between sputum neutrophils and systemic biomarkers were non-significant or similarly weak. The mean change over 1 year in neutrophil % was an increase of 3.5%.

Conclusions: Sputum neutrophil measurements in COPD are associated weakly with FEV1 % predicted and health status. Sputum neutrophil measurements were dissociated from exacerbation rates, emphysema and systemic inflammation.

Trial registration: ClinicalTrials.gov NCT00292552.

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Figures

Figure 1
Figure 1
Sputum neutrophil % shown according to GOLD stage at baseline and year 1. Medians (lines), interquartile ranges (boxes) and ranges (error bars) are shown.
Figure 2
Figure 2
Bland Altman plots of the mean measurements at baseline and 1 year (x-axis) and the difference between the measurements (year 1 - baseline shown on y-axis) for (a) log10 sputum neutrophil numbers/ml and (b) sputum neutrophil % counts.
Figure 3
Figure 3
Power calculations for a reduction in sputum neutrophil % in a parallel group study. Y axis is the number of subjects required. X axis is the effect size (e.g. 0.9 = 10% reduction).
See this image and copyright information in PMC

References

    1. Hogg JC, Chu F, Utokaparch S, Woods R, Elliott WM, Buzatu L, Cherniack RM, Rogers RM, Sciurba FC, Coxson HO, Paré PD. The nature of small-airway obstruction in chronic obstructive pulmonary disease. N Eng J Med. 2004;350:2645–2652. doi: 10.1056/NEJMoa032158. - DOI - PubMed
    1. The Global Initiative for Chronic Obstructive Lung Disease (GOLD) http://www.goldcopd.com
    1. Barnes PJ, Chowdhury B, Kharitonov SA, Magnussen H, Page CP, Postma D, Saetta M. Pulmonary biomarkers in chronic obstructive pulmonary disease. Am J Respir Crit Care Med. 2006;174:6–14. doi: 10.1164/rccm.200510-1659PP. - DOI - PubMed
    1. O'Donnell RA, Peebles C, Ward JA, Daraker A, Angco G, Broberg P, Pierrou S, Lund J, Holgate ST, Davies DE, Delany DJ, Wilson SJ, Djukanovic R. Relationship between peripheral airway dysfunction, airway obstruction, and neutrophilic inflammation in COPD. Thorax. 2004;59:837–42. doi: 10.1136/thx.2003.019349. - DOI - PMC - PubMed
    1. Keatings VM, Collins PD, Scott DM, Barnes PJ. Differences in interleukin-8 and tumor necrosis factor-alpha in induced sputum from patients with chronic obstructive pulmonary disease or asthma. Am J Respir Crit Care Med. 1996;153:530–4. - PubMed

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