Pulmonary Diseases and Critical Care Medicine, Department of Medicine, University of North Carolina School of Medicine, CB# 7020, 130 Mason Farm Rd, 4th Floor Bioinformatics Bldg, Chapel Hill, NC 27599, USA.
Respir Med. 2013 Jul;107(7):943-52. doi: 10.1016/j.rmed.2013.02.018. Epub 2013 Apr 17.
Until recently, no point-of-care tool was available for assessing the underlying airway inflammation associated with asthma. Fractional exhaled nitric oxide (FeNO) emerged in the last decade as an important biomarker for asthma assessment and management. Evidence also indicates that FeNO is most accurately classified as a marker of T-helper cell type 2 (Th2)-mediated airway inflammation with a high positive and negative predictive value for identifying corticosteroid-responsive airway inflammation. This manuscript evaluates the evidence for FeNO as a predictor of Th2-mediated corticosteroid-responsive airway inflammation and presents the results of a meta-analysis of three adult studies comparing asthma exacerbation rates with FeNO-based versus clinically-based asthma management algorithms, one of which was not included in a 2012 Cochrane meta-analysis. The primary purpose of the updated meta-analysis was to evaluate asthma exacerbation rates. The results demonstrate that the rate of exacerbations was significantly reduced in favor of FeNO-based asthma management (mean treatment difference = -0.27; 95% CI [-0.42, -0.12] as was the relative rate of asthma exacerbations (relative rate = 0.57; 95% CI [0.41, 0.80]). In summary, FeNO has value for identifying patients with airway inflammation who will and will not respond to corticosteroids. Importantly, the use of FeNO in conjunction with clinical parameters is associated with significantly lower asthma exacerbation rates compared with asthma managed using clinical parameters alone. Together these data indicate that FeNO testing has an important role in the assessment and management of adult asthma. Further studies will continue to define the exact role of FeNO testing in adult asthma.
直到最近，还没有可用于评估与哮喘相关的潜在气道炎症的即时检测工具。在过去十年中，呼出气一氧化氮分数（FeNO）作为评估和管理哮喘的重要生物标志物出现。有证据表明，FeNO 最准确地被归类为 T 辅助细胞 2（Th2）介导的气道炎症标志物，对识别皮质类固醇反应性气道炎症具有较高的阳性和阴性预测值。本文评估了 FeNO 作为 Th2 介导的皮质类固醇反应性气道炎症预测因子的证据，并介绍了三项成人研究的荟萃分析结果，这些研究比较了基于 FeNO 的与基于临床的哮喘管理算法的哮喘加重率，其中一项研究未包含在 2012 年 Cochrane 荟萃分析中。更新后的荟萃分析的主要目的是评估哮喘加重率。结果表明，基于 FeNO 的哮喘管理显著降低了哮喘加重的发生率（平均治疗差异=-0.27；95%CI [-0.42, -0.12]），哮喘加重的相对发生率也显著降低（相对比率=0.57；95%CI [0.41, 0.80]）。总之，FeNO 可用于识别气道炎症患者，这些患者对皮质类固醇有反应和无反应。重要的是，与仅使用临床参数管理哮喘相比，FeNO 与临床参数联合使用与哮喘加重率显著降低相关。这些数据表明，FeNO 检测在成人哮喘的评估和管理中具有重要作用。进一步的研究将继续定义 FeNO 检测在成人哮喘中的确切作用。
