呼出气一氧化氮和呼出气冷凝液 pH 值在哮喘控制评估中的应用。

Exhaled NO and exhaled breath condensate pH in the evaluation of asthma control.

机构信息

Respiratory Medicine Department, University of Thessaly Medical School, Larissa, Greece.

出版信息

Respir Med. 2011 Apr;105(4):526-32. doi: 10.1016/j.rmed.2010.10.015. Epub 2010 Nov 3.

DOI:10.1016/j.rmed.2010.10.015

PMID:21051211

Abstract

BACKGROUND

Asthma is a chronic inflammatory airways disorder. However, no biomarker of airways inflammation has been included in the assessment of asthma control.

OBJECTIVE

To evaluate exhaled NO (FeNO) and exhaled breath condensate (EBC) pH in patients with asthma according to the level of control, and their performance in the identification of not well-controlled patients.

METHODS

FeNO and EBC pH after Argon deaeration were measured in 274 consecutive patients. Asthma control was evaluated by two asthma specialists blinded to FeNO and pH measurements according to GINA guidelines, as well as by asthma control test (ACT) and asthma control questionnaire (ACQ).

RESULTS

FeNO was higher and EBC pH was lower in patients with not well-controlled compared to controlled asthma. In ROC analysis, FeNO presented an AUC of 0.790 for the identification of not well-controlled asthma performing better in non-smokers; EBC pH presented an AUC of 0.791 for the identification of not well-controlled asthma, performing better in smokers. The performance of both biomarkers was inferior to that of ACT and ACQ. FeNO values >30 ppb presented positive predictive values (PPV) > 0.85 with the exception of smokers treated with inhaled corticosteroids. EBC pH values ≤7.20 presented PPV >0.80 in all groups. The presence of FeNO >30 ppb and/or EBC pH ≤7.20 was indicative of not well-uncontrolled asthma in 88.3% of the patients.

CONCLUSION

FeNO and EBC pH levels may identify patients with not well-controlled asthma. However, their performance was inferior to clinical judgment and may be limited to selected subgroups of asthmatic patients.

摘要

背景

哮喘是一种慢性气道炎症性疾病。然而，目前尚无气道炎症的生物标志物被纳入哮喘控制的评估中。

目的

评估哮喘患者呼出气一氧化氮（FeNO）和呼出气冷凝液（EBC）pH 值与控制水平的关系，及其在识别控制不佳患者中的作用。

方法

对 274 例连续患者进行氩气脱气后的 FeNO 和 EBC pH 值测量。根据 GINA 指南，两名对 FeNO 和 pH 值测量结果不知情的哮喘专家以及哮喘控制测试（ACT）和哮喘控制问卷（ACQ）对哮喘控制进行评估。

结果

与控制良好的哮喘患者相比，控制不佳的哮喘患者的 FeNO 更高，EBC pH 值更低。在 ROC 分析中，FeNO 对识别控制不佳的哮喘的 AUC 为 0.790，在非吸烟者中表现更好；EBC pH 值对识别控制不佳的哮喘的 AUC 为 0.791，在吸烟者中表现更好。这两种生物标志物的性能均逊于 ACT 和 ACQ。FeNO 值>30 ppb 的阳性预测值（PPV）>0.85，除外吸入皮质激素治疗的吸烟者。EBC pH 值≤7.20 在所有组中的 PPV>0.80。在 88.3%的患者中，FeNO>30 ppb 和/或 EBC pH 值≤7.20 提示存在控制不佳的哮喘。