Abstract
Introduction: Fractional Exhaled Nitric Oxide (FeNO) has been shown to reduce asthma exacerbations in adults when used to guide the dosing of inhaled corticosteroids (ICS) in a recent meta-analysis (Donohue, J. et.al. Respir Med 2013). These studies focused on care delivered by specialists whereas a more recent study looked at the impact of FeNO directed ICS therapy in a primary care setting (Syk, J. et.al. J Allergy Clin Immunl Pract 2013).
Objective: To compare a recently published clinical trial to a meta-analysis of asthma exacerbation rates in adult studies evaluating asthma managed using FeNO versus standard clinical parameters alone.
Methods: Data from 3 adult studies by Shaw, Smith & Powell and the new adult study by Syk were analyzed in a meta-analysis.
Results: Across the 4 studies, there were a total of 302 subjects in the FeNO management group and 296 subjects in the control management group. Asthma exacerbation rates ranged from 0.22-0.49 and 0.41-0.9 across the FeNO and control management groups, respectively, and the exacerbation rate was significantly reduced in favor of the FeNO based management (-0.26 [-0.38, -0.15]). When these data were expressed as a relative rate, the rate of exacerbations was 44% lower with the FeNO-based asthma management strategy compared with the control asthma management strategy (0.56 [0.42, 0.74]).
Conclusion: Data from the Syk study are consistent with findings from the Shaw, Smith & Powell studies published in the Donohue meta-analysis. Across the 4 studies asthma exacerbations were reduced, providing evidence that FeNO directed therapy reduces asthma exacerbation.
- © 2014 ERS