RT Journal Article SR Electronic T1 Exhaled NO and assessment of anti-inflammatory effects of inhaled steroid: dose-response relationship JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP 601 OP 608 DO 10.1183/09031936.02.00285302 VO 20 IS 3 A1 S.L. Jones A1 P. Herbison A1 J.O. Cowan A1 E.M. Flannery A1 R.J. Hancox A1 C.R. McLachlan A1 D.R. Taylor YR 2002 UL http://erj.ersjournals.com/content/20/3/601.abstract AB Exhaled nitric oxide (eNO) is an easily measured marker of airway inflammation. This study was undertaken to evaluate the usefulness of serial eNO in investigating the dose-response relationship for inhaled beclomethasone (BDP), and to compare eNO with other markers of airway inflammation. Following withdrawal of inhaled corticosteroid (ICS) therapy, 65 patients entered a double-blind, parallel-group, placebo-controlled trial of 50, 100, 200 or 500 µg·BDP·day−1 for eight weeks. eNO and spirometry were performed weekly and a hypertonic saline challenge with sputum induction was performed at the beginning and end of treatment. The relationship between the dose of ICS and changes in eNO and forced expiratory volume in one second (FEV1) was linear at 1 week and at the end of treatment. A linear dose-response relationship was also seen for sputum eosinophils. Changes in eNO correlated significantly with changes in sputum eosinophils. Changes in the provocative dose of saline causing a 15% fall in FEV1 saline did not differ across the treatment groups nor did they correlate with changes in other measurements. Exhaled nitric oxide may be used to assess the dose-response relationship for the anti-inflammatory effects of inhaled beclomethasone. The relationship found in this study was linear over the dose range 0–500 µg·day−1 soon after commencing therapy and continued over time. This study was funded by the Health Research Council of New Zealand and by an Otago Research Grant administered by the University of Otago. S.L. Jones was supported by a GlaxoSmithKline (GSK) research fellowship, and GSK provided an educational grant.