Chest
Original ResearchCOPDPersistent Airway Inflammation and Emphysema Progression on CT Scan in Ex-Smokers Observed for 4 Years
Section snippets
Baseline Visits
Study and control subjects were recruited as part of a National Institutes of Health Biomarker study, and their clinical characteristics, pulmonary function, and selected biomarkers have previously been described in detail.16, 17 In brief, subjects with COPD-E were recruited based on clinical evaluation and chest CT scan evidence of emphysema, which had to be present to be included in the study, whereas control subjects were required to have no clinical evidence of COPD and a normal chest CT
Baseline COPD-E Study Subject CT Scan, Pulmonary Function
At the baseline visit, the subjects with COPD-E (n = 10) had a mean age of 69 ± 2 years, were clinically stable, and had a St. George Questionnaire mean score of 37 ± 10. Based on the GOLD criteria, the subjects with COPD-E had GOLD stage IIb moderate severity COPD (GOLD stage IIb; FEV1/FVC ratio < 0.70, and FEV1 ≤ 50% and ≥ 30% predicted).21
The subjects with COPD-E at the baseline visit all had evidence of significant emphysema based on their chest CT scan (Table 1). Subjects with COPD-E had
Discussion
This study demonstrated that ex-smokers with GOLD Stage IIb COPD-E who were followed for 4 years while not smoking have persistent airway inflammation detectable in sputum and progression of emphysema on chest CT scan. The mediators of inflammation that persisted at elevated levels in sputum included mediators associated with neutrophil-mediated inflammation (MPO, LTB4, IL-8), mediators associated with recruitment of mononuclear cells (MCP-1), and mediators associated with extracellular matrix
Acknowledgments
Author contributions: Dr Miller: contributed to processing and analyzing sputum samples, performing statistical analysis of results, and editing the manuscript.
Dr Cho: contributed to processing and analyzing sputum samples, performing statistical analysis of results, and editing the manuscript.
Ms Pham: contributed to processing and analyzing sputum samples, performing statistical analysis of results, and editing the manuscript.
Dr Friedman: contributed to interpreting and scoring of chest CT
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Funding/Support: This work was supported by the National Institutes of Health [Grants HL72342, and GCRC MO1RR000827].
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