This Article Full Text Full Text (PDF) Online Supplement All Versions of this Article: 200905-0685OCv1 180/9/846    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Dummer, J. F. Articles by Taylor, D. R. PubMed PubMed Citation Articles by Dummer, J. F. Articles by Taylor, D. R.

Predicting Corticosteroid Response in Chronic Obstructive Pulmonary Disease Using Exhaled Nitric Oxide

¹ Dunedin and Christchurch Schools of Medicine, University of Otago, Dunedin, New Zealand

Correspondence and requests for reprints should be addressed to Professor D. Robin Taylor, M.D., F.R.C.P.(C), Dunedin School of Medicine, University of Otago, P.O. Box 913, Dunedin, New Zealand. E-mail: robin.taylor{at}stonebow.otago.ac.nz

Rationale: Predicting corticosteroid response in COPD is important but difficult. Response is more likely to occur in association with eosinophilic airway inflammation, for which the fraction of exhaled nitric oxide (FE_NO) is a good surrogate marker.

Objectives: We aimed to establish whether FE_NO levels would predict the clinical response to oral corticosteroid in COPD.

Methods: We performed a double-blind, crossover trial of steroid in patients with COPD. After a 4-week washout of inhaled steroids, patients received prednisone 30 mg/d or matching placebo, in random order, with an intervening 4-week washout. The predictive values of FE_NO for clinically significant changes in 6-minute-walk distance (6MWD), spirometry (FEV₁), and St. George's Respiratory Questionnaire (SGRQ) were calculated.

Measurements and Main Results: A total of 65 patients (mean FEV₁ = 57% predicted) were randomized. With prednisone, there was a net increase of 13 m in 6MWD (P = 0.02) and 0.06 L in postbronchodilator FEV₁ (P = 0.02) compared with placebo. The change in SGRQ was not significant. Using receiver operator characteristic analysis, the area under the curve for an increase of 0.2 L in FEV₁ was 0.69 (P = 0.04) with an optimum FE_NO cut-point of 50 ppb. The positive and negative predictive values were 67 and 82%, respectively. FE_NO was not a significant predictor for changes in 6MWD or SGRQ.

Conclusions: FE_NO is a weak predictor of short-term response to oral corticosteroid in COPD, its usefulness being limited to predicting increase in FEV₁.

Clinical trial registered with www.anzctr.org.au (ACTRN12605000683639).

Key Words: exhaled nitric oxide • COPD • prednisone treatment response

AT A GLANCE COMMENTARY Scientific Knowledge on the Subject Only a minority of patients with chronic obstructive pulmonary disease (COPD) have steroid-responsive airway inflammation, and they are difficult to identify. Exhaled nitric oxide (FENO) predicts steroid response in patients with nonspecific airway symptoms. Its usefulness in COPD has not been systematically assessed. What This Study Adds to the Field FENO is a weak predictor of short-term steroid response in COPD, its usefulness being limited to predicting an increase in FEV1.