title: Gender and age affect the levels of exhaled nitric oxide in healthy children.
abstract: Asthma is a chronic inflammatory disorder of the lung and diagnosis is difficult in children. The measurement of fractional exhaled nitric oxide (FeNO) may be useful in the diagnosis and monitoring of treatments. A number of factors affect FeNO levels and their influence varies across countries and regions. This study included 300 healthy students, aged from 6 to 14 years, who participated voluntarily. A comprehensive medical survey was used and measurements of FeNO levels and spirometric parameters were recorded in Shenyang, China. We observed that the median FeNO was 11 ppb (range, 8-16 ppb) in children from the northern areas of China. For males, the median level was 13 ppb (range, 9-18 ppb) and the median level was 10 ppb (range, 8-14 ppb) for females. There was a significant difference between males and females (P= 0.007) and age was correlated with FeNO (R2= 0.6554), while weight, height, body mass index (BMI), forced vital capacity (FVC), forced expiratory volume (FEV1), FEV1/FVC and peak expiratory flow (PEF) had no correlation with FeNO. In conclusion, the median FeNO is 11 ppb (range, 8-16 ppb) in male and female healthy children from northern areas of China and is affected by gender and age.
authors.affiliation: Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China.
authors.forename: Han
authors.initials: H
authors.lastname: Zhang
authors.forename: Linhua
authors.initials: L
authors.lastname: Shu
authors.forename: Xuxu
authors.initials: X
authors.lastname: Cai
authors.forename: Zhijia
authors.initials: Z
authors.lastname: Wang
authors.forename: Xuyong
authors.initials: X
authors.lastname: Jiao
authors.forename: Fen
authors.initials: F
authors.lastname: Liu
authors.forename: Ping
authors.initials: P
authors.lastname: Hou
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.forename: Lishen
authors.initials: L
authors.lastname: Shan
authors.forename: Ning
authors.initials: N
authors.lastname: Chen
authors.forename: Yunxiao
authors.initials: Y
authors.lastname: Shang
keywords: age; exhaled nitric oxide; gender; healthy children