Ly Ngoc P, Soto-Quirós Manuel E, Avila Lydiana, Hunninghake Gary M, Raby Benjamin A, Laskey Daniel, Sylvia Jody S, Celedón Juan C
Channing Laboratory, 181 Longwood Ave, Boston, MA 02115, USA.
Chest. 2008 Jan;133(1):107-14. doi: 10.1378/chest.07-2130. Epub 2007 Nov 7.
Little is known about the determinants of airway hyperresponsiveness (AHR) among children with asthma in Hispanic America.
We examined the relations among selected familial and environmental factors, markers of allergy, spirometric measures of lung function, and AHR in a cross-sectional study of 403 Costa Rican children with asthma between the ages of 6 and 14 years. Study participants completed a protocol that included questionnaires, spirometry, measurements of serum total and allergen-specific IgE, peripheral blood eosinophil count, and body mass index, and the assessment of airway responsiveness to methacholine (ie, a methacholine challenge test [MCT]). AHR to MCT was defined as the provocative dose of methacholine causing a 20% fall in FEV(1). Linear regression was used for the univariate and multivariate analyses.
Of the 403 asthmatic children who underwent an MCT, 350 (86.8%) had AHR to methacholine. In a multivariate analysis, paternal asthma (p = 0.004), parental report of mold/mildew in the child's home (p = 0.04), FEV(1)/FVC ratio (p < 0.0001), and a positive IgE response to Der p 1 (p = 0.008) were significantly associated with AHR among Costa Rican children with asthma.
Our results suggest that paternal asthma and environmental exposure to mold/mildew are strong determinants of AHR in Costa Rican children with asthma. FEV(1)/FVC ratio may be a useful measure of AHR (a marker of asthma severity) among Costa Ricans and other Hispanic Americans for whom reference values for FEV(1) are not currently available.
关于拉丁美洲裔美国哮喘儿童气道高反应性（AHR）的决定因素知之甚少。
我们在一项横断面研究中，对403名年龄在6至14岁之间的哥斯达黎加哮喘儿童，研究了选定的家族和环境因素、过敏标志物、肺功能的肺量计测量值与AHR之间的关系。研究参与者完成了一项方案，包括问卷调查、肺量计检查、血清总IgE和过敏原特异性IgE测量、外周血嗜酸性粒细胞计数、体重指数，以及对乙酰甲胆碱的气道反应性评估（即乙酰甲胆碱激发试验[MCT]）。对MCT的AHR定义为导致FEV(1)下降20%的乙酰甲胆碱激发剂量。采用线性回归进行单变量和多变量分析。
在接受MCT的403名哮喘儿童中，350名（86.8%）对乙酰甲胆碱有AHR。在多变量分析中，父亲患哮喘（p = 0.004）、父母报告孩子家中有霉菌/霉变（p = 0.04）、FEV(1)/FVC比值（p < 0.0001），以及对Der p 1的IgE阳性反应（p = 0.008）与哥斯达黎加哮喘儿童的AHR显著相关。
我们的结果表明，父亲患哮喘和环境中接触霉菌/霉变是哥斯达黎加哮喘儿童AHR的重要决定因素。对于目前尚无FEV(1)参考值的哥斯达黎加人和其他拉丁美洲裔美国人，FEV(1)/FVC比值可能是AHR（哮喘严重程度的一个指标）的有用测量指标。
