Exhaled nitric oxide in healthy nonatopic school-age children: Determinants and height-adjusted reference values.

摘要

Exhaled nitric oxide (FE(NO)) was proposed as a marker of airway inflammation, but data about FE(NO) in healthy children measured with standardized methods are so far limited. In order to assess the determinants of FE(NO) in healthy children, we investigated a population-based sample of school-age children (n = 276) with a questionnaire, skin-prick tests, spirometry, and the measurement of FE(NO). The FE(NO) of 114 nonatopic and nonsmoking children considered healthy were analyzed with stepwise multiple regression analysis, which showed significant associations with age, standing height, weight, and body surface area, but not with gender. Height was found to be the best independent variable for the regression equation for FE(NO), which on average showed an increase in the height range of 120-180 cm from 7 to 14 ppb. In the random sample of children, increased FE(NO) was associated with atopy (odds ratio, 9.0; 95% confidence interval, 3.9-21.1; P < 0.0001), and significantly with allergic rhinitis and atopic dermatitis, but not with asthma. Respiratory symptom-free children with skin-prick test positivity had significantly higher FE(NO) than healthy nonatopic subjects. We conclude that height is the best determinant of FE(NO) in healthy children. Due to the strong effect of atopy, FE(NO) data should not be interpreted without knowing the atopic status of the child. The present reference values of FE(NO) may serve in clinical assessments for measuring airway inflammation in children. Pediatr Pulmonol. 2006; 41: 635-642. (c) 2006 Wiley-Liss, Inc.