Exhaled NO and assessment of anti-inflammatory effects of inhaled steroid: dose-response relationship

Abstract

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 mg?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 antiinflammatory effects of inhaled beclomethasone. The relationship found in this study was linear over the dose range 0-500 mg?day -1 soon after commencing therapy and continued over time. Eur Respir J 2002; 20: 601-608.

Features of severe asthma in school-age children: Atopy and increased exhaled nitric oxide

“…16,22 In subjects with mild asthma, F ENO correlates with the magnitude of airway eosinophilia 23 and bronchial hyper-responsiveness 24 and falls in a dose-dependent manner after the initiation of ICS. 25 Accordingly, F ENO in our study was lower in children with mild-to-moderate asthma treated with lower doses of ICS than in children with severe asthma on twice the amount of daily ICS. Similar findings have been reported by others 5,26 and suggest that persistent airway inflammation may be a defining feature of at least a subpopulation of children with severe asthma.…”

Exhaled nitric oxide and asthma control: a longitudinal study in unselected patients

“…Indeed, it has been shown that for ICS doses ,500 mg BDPeq?day -1 , the relationship between FeNO and the antiinflammatory effect of ICS is linear, while at doses of .500 mg BDPeq?day -1 FeNO levels may be low despite ongoing airway inflammation [15,16]. In the latter group (i.e.…”

Monitoring sputum eosinophils in mucosal inflammation and remodelling: a pilot study

“…Various new strategies have been recently proposed to determine treatment needs using noninvasive measures of airway inflammation, such as those based on exhaled nitric oxide and induced sputum analysis, in order to improve asthma monitoring and optimise the treatment of asthma [10,19,20]. Previously, GREEN et al [9] have shown that a treatment strategy adjusting the dose of ICS to reduce airway eosinophilia resulted in better asthma control when compared to the usual British Thoracic Society guidelines.…”