de Meer G, Marks G B, de Jongste J C, Brunekreef B
Institute for Risk Assessment Sciences, Environmental and Occupational Health, Utrecht University, P Box 80176, 3508 TD Utrecht, The Netherlands.
Eur Respir J. 2005 Jan;25(1):153-8. doi: 10.1183/09031936.04.00008004.
The result of airway challenge test with hypertonic saline (HS) is expressed as the dose causing a 15% fall in forced expiratory volume in one second (FEV1; PD15). A noncensored measure, such as the dose-response slope (DRS), allows the evaluation of the risk of asthma for subjects with a fall in FEV1 <15%. The aim of this study was to assess the relationship between airway responsiveness to HS by PD15 or DRS, asthma symptoms and markers of eosinophilic inflammation. Data on current wheeze and airway responsiveness were obtained for 1,107 children (aged 8-13 yrs). Blood eosinophils and serum eosinophil cationic protein (ECP) were assessed in subsets (n = 683 and 485). PD15 was assessed if FEV1 fell > or =15%, and the DRS was calculated for all tests. Graphs were constructed to visualise relationships with current wheeze, blood eosinophils and serum ECP. Odds ratios and Spearman's correlation coefficients were calculated to quantify these relationships. Children with features of asthma had lower PD15 and higher DRS, and separation was most pronounced for DRS. Prevalence of current wheeze increased continuously over the entire range of DRS values. Blood eosinophils were significantly higher only for the highest values of DRS. In conclusion, the continuous relationship between airway responsiveness and asthma symptoms is in favour of a noncensored measure of airway responsiveness, such as the dose-response slope.
用高渗盐水（HS）进行气道激发试验的结果表示为导致一秒用力呼气容积（FEV1；PD15）下降15%的剂量。一种非删失测量方法，如剂量反应斜率（DRS），可用于评估FEV1下降<15%的受试者患哮喘的风险。本研究的目的是评估通过PD15或DRS评估的气道对HS的反应性、哮喘症状与嗜酸性粒细胞炎症标志物之间的关系。获取了1107名儿童（8 - 13岁）目前喘息情况和气道反应性的数据。对部分儿童（n = 683和485）评估了血液嗜酸性粒细胞和血清嗜酸性粒细胞阳离子蛋白（ECP）。如果FEV1下降≥15%，则评估PD15，并对所有测试计算DRS。绘制图表以直观显示与目前喘息、血液嗜酸性粒细胞和血清ECP的关系。计算比值比和Spearman相关系数以量化这些关系。具有哮喘特征的儿童PD15较低而DRS较高，且DRS的差异最为明显。在整个DRS值范围内，目前喘息的患病率持续增加。仅在DRS最高值时血液嗜酸性粒细胞显著升高。总之，气道反应性与哮喘症状之间的连续关系支持采用非删失的气道反应性测量方法，如剂量反应斜率。
