Low exhaled nitric oxide in school-age children with bronchopulmonary dysplasia and airflow limitation.
Bronchopulmonary dysplasia (BPD), the chronic lung disease of prematurity, may be associated with long-term airflow limitation. Survivors of BPD may develop asthma-like symptoms in childhood, with a variable response to beta(2)-agonists. However, the pathologic pathways underlying these respiratory manifestations are still unknown. The aim of this study was to measure exhaled nitric oxide (FE(NO)) and lung function in a group of 31 school-age survivors of BPD. They showed variable degrees of airflow obstruction (mean FEV(1) 77.8 +/- 2.3% predicted) unresponsive to beta(2)-agonists in 72% of the subjects. Their FE(NO) values (geometric mean [95% confidence interval]: 7.7 [+/- 1.1] ppb) were significantly lower than in a group of healthy matched control subjects born at term (10.7 [+/- 1.1] ppb, p < 0.05) and a group of preterm children without BPD (9.9 [+/- 1.1] ppb, p < 0.05). The children with BPD were also compared with a group of 31 patients with asthma with a comparable airflow limitation (FEV(1) 80.2 +/- 2.1% predicted) and showed FE(NO) values four times lower than in those with asthma (24.9 [+/- 1.2] ppb, p < 0.001). In conclusion, unlike children with asthma, school-age survivors of BPD have airflow limitation associated with low FE(NO) values and lack of reversibility to beta(2)-agonists, probably as a result of mechanisms related to early life structural changes in the airways.
Baraldi
Eugenio
E
Department of Pediatrics, School of Medicine, University of Padova, Via Giustiniani 3, 35128 Padova, Italy. baraldi@pediatria.unipd.it
Bonetto
Gea
G
Zacchello
Franco
F
Filippone
Marco
M
D000318:Adrenergic beta-Agonists / Q000627:therapeutic use; D001249:Asthma / Q000503:physiopathology; D001944:Breath Tests; D001997:Bronchopulmonary Dysplasia / Q000276:immunology / Q000378:metabolism / Q000503:physiopathology*; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D005541:Forced Expiratory Volume; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007428:Intradermal Tests; D008297:Male; D008450:Maximal Midexpiratory Flow Rate; D009569:Nitric Oxide / Q000032:analysis*; D012123:Pulmonary Ventilation / Q000187:drug effects; D012135:Respiratory Sounds; D013147:Spirometry; D014797:Vital Capacity
D000318:Adrenergic beta-Agonists; D009569:Nitric Oxide