Exhaled nitric oxide and exercise-induced bronchospasm assessed by FEV1, FEF25-75% in childhood asthma.
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.
Nishio
Ken
K
Department of Pediatrics, Fukuoka National Hospital, and Fukuoka University, School of Medicine, Japan.
Odajima
Hiroshi
H
Motomura
Chikako
C
Nakao
Fumiya
F
Nishima
Sankei
S
D001249:Asthma / Q000378:metabolism / Q000503:physiopathology; D001250:Asthma, Exercise-Induced / Q000175:diagnosis / Q000378:metabolism / Q000503:physiopathology*; D001944:Breath Tests; D002648:Child; D005080:Exercise Test; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology*; D006801:Humans; D008297:Male; D008450:Maximal Midexpiratory Flow Rate / Q000502:physiology*; D009569:Nitric Oxide / Q000378:metabolism*; D011237:Predictive Value of Tests; D013147:Spirometry
D009569:Nitric Oxide