Tsuburai Takahiro, Tsurikisawa Naomi, Taniguchi Masami, Morita Sonoko, Ono Emiko, Oshikata Chiyako, Ohtomo Mamoru, Maeda Yuji, Ikehara Kunihiko, Akiyama Kazuo
Clinical Research Center for Allergy and Rheumatology, National Hospital Organization, Sagamihara National Hospital, Kanagawa, Japan.
Allergol Int. 2007 Mar;56(1):37-43. doi: 10.2332/allergolint.O-06-439. Epub 2007 Jan 29.
Exhaled nitric oxide (eNO) is a useful marker of eosinophilic airway inflammation in asthma patients. There is no study to show the relationship between the eNO measured by using an off-line method and the degree of reversibility of airflow limitation in Japanese asthma patients. We sought to investigate the relationship between the eNO level measured by using an off-line method and the degree of reversibility of bronchial constriction in Japanese asthma patients.
The study population comprised 97 asthma patients in our outpatient clinic with some patients in both groups who received inhaled corticosteroid treatment. We measured eNO levels, forced expiratory volume in one second (FEV1) before and after treatment, reversible airway obstruction (DeltaFEV1) after inhalation of bronchodilator, and other parameters.
eNO was significantly correlated with peripheral blood eosinophil counts in asthma patients (in steroid-naïve asthma patients, r=0.544, p<0.0001; in asthma patients treated with inhaled corticosteroid, r=0.463, p=0.026), and subjects with severe eosinophilia in sputum showed high levels of eNO (mild eosinophilia versus severe, p=0.0152). Among patients with obstructive impairment, eNO levels were correlated with DeltaFEV1 regardless of whether patients received (r=0.527, p=0.0435) or did not receive (r=0.64, p = 0.0056) inhaled corticosteroid. In subjects with normal pulmonary function, there was no significant relationship between eNO and DeltaFEV1 with or without inhaled corticosteroid.
In patients with obstructive impairment, eNO reflects the degree of reversible airflow limitation. In subjects with normal pulmonary function, eNO may facilitate the diagnosis and management of asthma, rather than indicate reversible bronchial obstruction. eNO measurement by off-line methods is applicable as a potential tool for the diagnosis of asthma and management of asthma patients.
呼出一氧化氮（eNO）是哮喘患者嗜酸性气道炎症的有用标志物。尚无研究表明在日本哮喘患者中，采用离线方法测量的eNO与气流受限可逆程度之间的关系。我们试图研究在日本哮喘患者中，采用离线方法测量的eNO水平与支气管收缩可逆程度之间的关系。
研究人群包括我们门诊的97例哮喘患者，两组中均有部分患者接受吸入性糖皮质激素治疗。我们测量了eNO水平、治疗前后的一秒用力呼气容积（FEV1）、吸入支气管扩张剂后的可逆性气道阻塞（ΔFEV1）以及其他参数。
哮喘患者的eNO与外周血嗜酸性粒细胞计数显著相关（在未使用类固醇的哮喘患者中，r = 0.544，p < 0.0001；在接受吸入性糖皮质激素治疗的哮喘患者中，r = 0.463，p = 0.026），痰液中嗜酸性粒细胞增多严重的受试者eNO水平较高（轻度嗜酸性粒细胞增多与严重嗜酸性粒细胞增多相比，p = 0.0152）。在阻塞性损害患者中，无论患者是否接受（r = 0.527，p = 0.0435）或未接受（r = 0.64，p = 0.0056）吸入性糖皮质激素治疗，eNO水平均与ΔFEV1相关。在肺功能正常的受试者中，无论是否使用吸入性糖皮质激素，eNO与ΔFEV1之间均无显著关系。
在阻塞性损害患者中，eNO反映了气流受限的可逆程度。在肺功能正常的受试者中，eNO可能有助于哮喘的诊断和管理，而非提示可逆性支气管阻塞。采用离线方法测量eNO可作为哮喘诊断和哮喘患者管理的潜在工具。
