Articles |

Exhaled Nitric Oxide and Induced Sputum Analysis as Markers of Airway Inflammation in Subjects With COPD* FREE TO VIEW

Philip E. Silkoff, MD; D. Martin; Juno Pak, BS; Richard J. Martin, MD, FCCP
Author and Funding Information

*From the National Jewish Medical and Research Center, University of Colorado Health Sciences Center, Denver, CO.

Correspondence to: Philip E. Silkoff, MD, National Jewish Medical and Research Center, University of Colorado Health Sciences Center, 1400 Jackson St, Denver, CO 80206

Chest. 2000;117(5_suppl_1):281S. doi:10.1378/chest.117.5_suppl_1.281S
Text Size: A A A
Published online

Abbreviations: Feno = exhaled nitric oxide; IL = interleukin; IS = induced sputum; LTB4 = leukotriene B4

Background: Airway inflammation is an important mechanism underlying deterioration in COPD and can be noninvasively assessed by exhaled nitric oxide (Feno) and induced sputum (IS). We wished to examine the short-term reproducibility of Feno and IS in a cohort of subjects with COPD.

Methods: We recruited 11 subjects (9 men; age, 46 to 69 years) with COPD (American Thoracic Society criteria) and FEV1 45 to 70% predicted. Feno and spirometry were assessed at baseline, 2, 4, and 6 weeks, and IS for differential cell count, leukotriene B4 (LTB4) and interleukin (IL)-8 at baseline, 4, and 6 weeks.

Results: There was a significant decline in FEV1 (p = 0.029) and FEV1/FVC ratio (p = 0.001) over the study period. This was accompanied by a significant increase (geometric mean with 95% confidence limits) from 15.2 (10.9 to 21.2) to 23.6 (17.1 to 32.4) parts per billion (p = 0.037) and LTB4 from 1.79 (1.03 to 3.11) to 3.57 (1.95 to 6.53) pg/mL (p = 0.018). There was no significant change in total or differential cell counts or IL-8 for the group as a whole; however, the change in both Feno and IL-8 correlated with the change in percent neutrophil count (r = 0.648, p = 0.028) and (r = 0.60, p = 0.05). Additionally, IL-8 and percent neutrophil count showed a borderline correlation (r = 0.34, p = 0.056). Finally, FEV1 showed a strong negative correlation with percent neutrophil count (r = 0.55, p = 0.001). The induction of sputum was well tolerated by all subjects, although FEV1 fell significantly from 1.83 ± 0.44 to 1.46 ± 0.44 L.

Conclusion: The worsening lung function over the study period, perhaps related to seasonal/climatic change, was accompanied by a significant increase in Feno and LTB4. Feno may be related to neutrophil inflammation, which is driven by the chemoattractant IL-8. Feno and IS promise to be useful markers of airway inflammation in COPD but IS causes a significant fall in FEV1 requiring careful monitoring and appropriate caution.




Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Find Similar Articles
CHEST Journal Articles
PubMed Articles
  • CHEST Journal
    Print ISSN: 0012-3692
    Online ISSN: 1931-3543