TY - JOUR T1 - Domiciliary diurnal variation of fractional exhaled nitric oxide (FeNO) to monitor asthma control JF - European Respiratory Journal JO - Eur Respir J VL - 42 IS - Suppl 57 SP - P4158 AU - Junpei Saito AU - David Gibeon AU - Patricia Macedo AU - Andrew Menzies-Gow AU - Pankaj Bhavsar AU - Fan Chung Y1 - 2013/09/01 UR - http://erj.ersjournals.com/content/42/Suppl_57/P4158.abstract N2 - Background:A major goal of asthma management is achieving and maintaining optimal control. Current assessment is based on symptoms and lung function. Portable monitors for FeNO have now become available.Objectives:We evaluated whether domiciliary daily home FeNO monitoring could be useful as an index of asthma control.Methods:Fifty asthmatic subjects and 15 healthy volunteers with a range of asthma severity underwent asthma control questionnaire (ACQ), spirometry before and after salbutamol and sputum induction. FeNO and peak expiratory flow (PEF) were measured twice daily for 2 weeks. A record of exacerbations was obtained 3 months later.Results:Diurnal FeNO variation in uncontrolled asthmatics was significantly greater than in controlled asthmatics (p<0.01). PEF variation was not different. The daily variation of FeNO levels was also greater in uncontrolled asthmatics compared to controlled asthmatic and healthy subjects (p<0.01). 80% of uncontrolled asthmatics experienced at least one or more exacerbations over the 3 months after the enrolment. The combination of diurnal FeNO variation ≥16.6% and ACQ scores ≤ 1.8 was best at predicting uncontrolled asthma (AUC; 0.91, 95%CI: 0.86-0.97, p<0.001).Conclusions:Diurnal variation in FeNO combined with ACQ scores can be used as a better marker of asthma control and as a predictor of the risk of future exacerbation. Prospective studies are warranted. ER -