Division of Allergy and Clinical Immunology, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
Department of Preventive Medicine, Korea University College of Medicine, Seoul, Korea.
J Allergy Clin Immunol. 2017 Sep;140(3):701-709. doi: 10.1016/j.jaci.2016.11.037. Epub 2017 Jan 11.
Individual studies have suggested the utility of fractional exhaled nitric oxide (Feno) measurement in detecting cough-variant asthma (CVA) and eosinophilic bronchitis (EB) in patients with chronic cough.
We sought to obtain summary estimates of diagnostic test accuracy of Feno measurement in predicting CVA, EB, or both in adults with chronic cough.
Electronic databases were searched for studies published until January 2016, without language restriction. Cross-sectional studies that reported the diagnostic accuracy of Feno measurement for detecting CVA or EB were included. Risk of bias was assessed with Quality Assessment of Diagnostic Accuracy Studies 2. Random effects meta-analyses were performed to obtain summary estimates of the diagnostic accuracy of Feno measurement.
A total of 15 studies involving 2187 adults with chronic cough were identified. Feno measurement had a moderate diagnostic accuracy in predicting CVA in patients with chronic cough, showing the summary area under the curve to be 0.87 (95% CI, 0.83-0.89). Specificity was higher and more consistent than sensitivity (0.85 [95% CI, 0.81-0.88] and 0.72 [95% CI, 0.61-0.81], respectively). However, in the nonasthmatic population with chronic cough, the diagnostic accuracy to predict EB was found to be relatively lower (summary area under the curve, 0.81 [95% CI, 0.77-0.84]), and specificity was inconsistent.
The present meta-analyses indicated the diagnostic potential of Feno measurement as a rule-in test for detecting CVA in adult patients with chronic cough. However, Feno measurement may not be useful to predict EB in nonasthmatic subjects with chronic cough. These findings warrant further studies to validate the roles of Feno measurement in clinical practice of patients with chronic cough.
个别研究表明，检测呼出气一氧化氮（Feno）在检测慢性咳嗽患者中的咳嗽变异型哮喘（CVA）和嗜酸性粒细胞性支气管炎（EB）方面具有一定的作用。
我们旨在评估 Feno 检测对成人慢性咳嗽患者 CVA、EB 或两者均有的预测诊断准确性。
我们检索了截至 2016 年 1 月的电子数据库，不限制语言。纳入了报告 Feno 检测对 CVA 或 EB 检测诊断准确性的横断面研究。采用 QUADAS-2 工具对研究的偏倚风险进行评估。应用随机效应模型进行荟萃分析，以获取 Feno 检测诊断准确性的综合估计值。
我们共纳入了 15 项涉及 2187 例慢性咳嗽成人患者的研究。Feno 检测对慢性咳嗽患者 CVA 的预测具有中等诊断准确性，曲线下面积综合估计值为 0.87（95%CI，0.83-0.89）。特异性优于敏感性（0.85 [95%CI，0.81-0.88]和 0.72 [95%CI，0.61-0.81]），且更一致。然而，在非哮喘慢性咳嗽患者中，预测 EB 的诊断准确性相对较低（曲线下面积综合估计值为 0.81 [95%CI，0.77-0.84]），且特异性不一致。
本荟萃分析表明，Feno 检测对慢性咳嗽成年患者 CVA 的检测具有一定的诊断价值，可作为一种阳性预测指标。然而，Feno 检测可能对非哮喘慢性咳嗽患者的 EB 预测没有作用。这些发现需要进一步的研究来验证 Feno 检测在慢性咳嗽患者临床实践中的作用。
