Exhaled nitric oxide predicts control in patients with difficult-to-treat asthma

Abstract

We aimed to evaluate the accuracy of baseline exhaled nitric oxide fraction (FeNO) to recognise individuals with difficult-to-treat asthma who have the potential to achieve control with a guideline-based stepwise strategy.102 consecutive patients with suboptimal asthma control underwent stepwise increase in the treatment with maximal fluticasone/salmeterol combination dose for 1 month. Then, those who remained uncontrolled received oral corticosteroids for an additional month.With this approach, 53 patients (52%) gained control. Those who achieved control were more likely to have positive skin results (60.4% versus 34%; p50.01), positive bronchodilator test (57.1% versus 35.8%; p50.02) and peak expiratory flow variability o20% (71.1% versus 49.1%; p50.04). Conversely, depression was more frequent in those who remained uncontrolled (18.4 % versus 43.4 %; p50.01). An FeNO value o30 ppb demonstrated a sensitivity of 87.5% (95% CI 73.9-94.5%) and a specificity of 90.6% (95% CI 79.7-95.9%) for the identification of responsive asthmatics.The current results suggest that FeNO can identify patients with difficult-to-treat asthma and the potential to respond to high doses of inhaled corticosteroids or systemic steroids.

Inhibition of the asthmatic allergen challenge response by the CRTH2 antagonist OC000459

“…Exhaled nitric oxide is a biomarker of asthma control, with levels being raised in symptomatic asthma and reduced by inhaled corticosteroids [23]. However, nitric oxide itself does not appear to play a pathophysiological role in asthma, as specific inducible nitric oxide synthase inhibition does not inhibit the allergen challenge response [8].…”

Intérêt de la mesure de l’inflammation en clinique dans l’asthme

“…Cette étude a mis en évidence un seuil de 47 ppb comme permettant de prédire une réponse au traitement stéroïdien [81] . Une autre étude récente suggère que la mesure du FE NO permet l'identification de patients ayant un asthme difficile à traiter et le potentiel de réponse de ces patients à des doses élevées de corticostéroïdes inhalés ou systémiques [100] . De plus, il semble que lorsque le patient ne présente pas d'éosinophilie bronchique, le FE NO reste hautement prédicteur d'une réponse aux corticostéroïdes avec une valeur seuil de 33 ppb [101] .…”

Guideline-Recommended Fractional Exhaled Nitric Oxide Is a Poor Predictor of Health-care Use Among Inner-city Children and Adolescents Receiving Usual Asthma Care

“…While studies in adults might be slightly more encouraging, 10,24,30 studies in school-age children have not strongly supported the use of F eno data in asthma management. 1,20,24,[31][32][33] A large clinical trial of innercity adolescents with asthma found that adding F eno level as an indicator of asthma control resulted in higher doses of ICS without clinical benefi t. 1 The present means to predict clinical deterioration or improvement beyond the traditionally available tests in a subspecialty offi ce setting.…”