Exhaled nitric oxide and exercise-induced bronchospasm assessed by FEV1, FEF25-75% in childhood asthma
ABSTRACT The relationship between exhaled nitric oxide (eNO) and bronchial hyperresponsiveness (BHR) should be clarified. The aim of this study was to determine the relationship between eNO and exercise-induced bronchospasm (EIB) by estimation of the each lung parameter in asthmatic children who performed a bicycle ergometer exercise test. Twenty children with asthma were recruited. eNO concentration was examined by the recommended online method. To evaluate BHR, an exercise stress test was performed on a bicycle ergometer. The mean baseline eNO value was significantly correlated with the mean maximum % fall in forced expiratory volume in 1 second (FEV1), forced expiratory flow between 25% and 75% (FEF25-75%) after exercise (r=0.53, r=0.65, respectively). eNO in the EIB-positive group was significantly higher than that in the EIB-negative group by assessing FEV1, FEF25-75% (p<0.005, p=0.005). We demonstrated that the most important lung parameter assessed the occurrence of EIB by a bicycle ergometer exercise test was not only FEV1 but FEF25-75%, which significantly correlated with eNO. This suggests that not only FEV1 but FEF25-75% can be used to evaluate the correlations between BHR (EIB) and airway inflammation (eNO) in asthmatic children. A low eNO is useful for a negative predictor for EIB.
Pediatric Allergy, Immunology, and Pulmonology 09/2011; 24(3):149-157. DOI:10.1089/ped.2011.0066 · 0.56 Impact Factor
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ABSTRACT: Our study tried to find a relationship between baseline FEF25-75% and airway hyperresponsiveness (AHR) and whether a greater FEF25-75% impairment may be a marker of a more severe hyperresponsiveness in subjects with normal FEV1 and FEV1/FVC and suggestive asthma symptoms. Besides, we tried to asses a FEF25-75% cut-off value to identify hyper-reactive subjects.Allergy, asthma & immunology research 05/2014; 6(3):242-51. DOI:10.4168/aair.2014.6.3.242 · 3.08 Impact Factor
Pediatric Allergy, Immunology, and Pulmonology 09/2013; 26(3):115-121. DOI:10.1089/ped.2013.0232 · 0.56 Impact Factor