PT  - JOURNAL ARTICLE
AU  - Tomasz Grzelewski
AU  - Paweł Majak
AU  - Joanna Jerzyńska
AU  - Włodzimierz Stelmach
AU  - Rafał Stelmach
AU  - Anna Janas
AU  - Aleksandra Grzelewska
AU  - Konrad Witkowski
AU  - Eusebio Makandjou-Ola
AU  - Iwona Stelmach
TI  - The interpretation of exhaled nitric oxide values in children with asthma depends on the degree of bronchoconstriction and the levels of asthma severity.
AID  - 10.4187/respcare.02889
DP  - 2013 Dec 31
TA  - Respiratory Care
PG  - respcare.02889
4099  - http://rc.rcjournal.com/content/early/2014/03/18/respcare.02889.short
4100  - http://rc.rcjournal.com/content/early/2014/03/18/respcare.02889.full
AB  - Introduction: The clinical implications of FeNO measurements in childhood asthma are unclear. Aim: We aimed to evaluate the relationship between the level of exhaled nitric oxide and pre-bronchodilator FEV1 and the change in FEV1 after bronchodilator in children with asthma. Methods: It was a retrospective, cross-sectional study. We evaluated data from medical documentation of children with asthma with special attention to FeNO results, asthma severity, FEV1 (% predicted), and bronchial reversibility test (BRT). Results: Four hundred and five subjects (aged 6-18) completed the study. Median levels of FeNO increased linearly with subjects' age (p=0.025). We found a non-linear trend of pre-bronchodilator FEV1 across four quartiles of FeNO in episodic and mild asthma; we observed lower pre-bronchodilator FEV1 in children with higher FeNO, but only up to the FeNO value of 35.4 ppb; in children with FeNO value higher than 35.4 ppb, pre-bronchodilator FEV1 was increased. We found a linear increasing trend of change from baseline (after 400 mcg of salbutamol) in FEV1 across FeNO categories in children with moderate asthma. Conclusions: Our results suggest a need to measure FeNO before as well as after spirometry. Consequently, in children with asthma with bronchial obstruction we suggest assessing FeNO also after short-acting Beta2-agonists.