Study of fractional exhaled nitric oxide concentrations in healthy school children of Beijing, Tianjin, Hebei province / 中国耳鼻咽喉头颈外科

ABSTRACT

OBJECTIVE To investigate the normal range of fraction exhaled nitric oxide(FeNO) in healthy schoolchildren in Beijing, Tianjin and Hebei Province. METHODS A total of 337 schoolchildren(161 males and 176 females) in Beijing, Tianjin and Hebei Province were selected randomly in our outpatient clinic and met the health standards. FeNO values were measured using NIOX. Age, height, weight and body mass index(BMI) were investigated. At the same time, skin prick tests were performed on children with suspected atopy. RESULTS Geometric mean of FeNO value in healthy schoolchildren in Beijing, Tianjin and Hebei Province was 13 ppb(part per billion, ppb), and the 95％ Confidence Interval(CI, bias distribution) was 5-23 ppb, which was related to the gender of schoolchildren(P ＜0.001). There was no signif icant cor relation between age, height, weight, body mass index(BMI) and regional differences(P all＞0.05). FeNO values were no significant difference among the three regions(P ＞0.05); the geometric mean of FeNO values were 13 ppb in Beijing, 13 ppb in Tianjin, and 14 ppb in Hebei; 95％CI was 5 to 21 ppb, 5 to 21 ppb, 5 to 23 ppb, respectively. CONCLUSION FeNO values of healthy schoolchildren in Beijing, Tianjin and Hebei provinces are only significantly correlated with gender. However, FeNO values are highest among schoolaged girls in Hebei, and 23 ppb is the 95％ normal range of FeNO in healthy schoolchildren in Beijing, Tianjin and Hebei province. Gender and regional factors must be considered when FeNO values are evaluated.