The correlation between fraction of exhaled nitric oxide and lung function in asthmatic children

Objective To investigate the correlation between exhaled nitric oxide and lung function (FEV1)in asthmatic children.Methods Fifty three stable asthmatic children aged 5 to 14 years old were recruited from ShengJing Hospital of China Medical University.According to whether the patients were treated with inhaled corticosteroid(ICS)therapy regularly,they were divided into two groups:steroid group and non-steroid group,then fraction of exhaled nitric oxide(FeNO)and lung function were measured.Results In non-steroid group,the levels of FeNO(mean 40.450±25.428 part by billion)were significantly higher than those in the steroid group(mean 19.879±13.845 part by billion),and they were statistically significant.(P = 0.003).The mean FEVI in non-steroid group was(95.152±8.993)%,and the mean FEVI in non-steroid group was(91.350±11.690)%,and there were no significant differences between two groups (P =0.189).Significantly negative correlation was found between FeNO and FEV1 in steroid group(r =-0.465,P = 0.039),but there was no significant correlation between them in steroid group(r = 0.058,P =0.747).Conclusion The levels of FeNO were higher in non-steroid group than those of the steroid group in the stable asthmatic children.FeNO is a good biomarker to evaluate the airway inflammation of asthmatic children. Key words: Bronchial asthma ;  Exhaled nitric oxide ;  Lung function ;