Response of exhaled nitric oxide to inhaled corticosteroids in patients with stable COPD: A systematic review and meta-analysis

• Published in: Clinical Respiratory Journal
• Main Author: Lim C.-S.; Rani F.A.; Tan L.-E.
• Format: Article
• Language: English
• Published: Blackwell Publishing Ltd 2018
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84978080314&doi=10.1111%2fcrj.12518&partnerID=40&md5=f1ac04eb123724a9d9274153d902df7d

Introduction: To our knowledge, no meta-analysis has investigated the response of FeNO levels to corticosteroid treatment in ex-smokers with chronic obstructive pulmonary disease (COPD). Objectives: This meta-analysis assessed the potential role of fraction of exhaled nitric oxide (FeNO) as a biomarker for corticosteroid response in ex-smokers with stable COPD. Methods: Medline, Cochrane, EMBASE, Google Scholar databases were searched until November 5, 2014 using the following terms: corticosteroid, chronic obstructive pulmonary disease, COPD, nitric oxide, NO, exhaled nitric oxide. Only randomized controlled trials (RCT) or two-arm prospective studies were included. The primary outcome measure was FeNO before and after treatment with inhaled corticosteroids (ICS) in ex-smokers with COPD. Sensitivity analysis was also performed. Results: Five studies were included in the analysis with a total of 171 COPD patients. All five studies included 125 ex-smokers and two of these also included 46 current smokers. There was a significant decrease of FeNO in ex-smoking COPD patients following inhaled corticosteroid treatment (−7.51, 95% CI: −11.51 to −3.51; P =0.003); and in a population of subjects that included both smokers and ex-smokers (−1.99, 95% CI: −3.41 to −0.56; P =0.006). Conclusion: Our findings indicate that FeNO levels significantly decreased with corticosteroid treatment in ex-smokers with COPD. Additional studies are required to evaluate whether concurrent smoking has significant effect on FeNO response to ICS. © 2016 John Wiley & Sons Ltd