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

Abstract

Objective To investigate the correlation with lung function and clinical significance of lung function and exhaled nitric oxide(FeNO) changes in various disease stages for children with asthma. Methods Seventy-nine asthma outpatient children aged 6-14 years old were selected from Nanjing Children's Hospital Affiliated to Nanjing Medical University, 25 cases of whom were at acute exacerbation stage, 28 cases at chronic persistent stage and 26 cases at remission stage.Twenty-five healthy children were randomly selected as the healthy control group, for whom FeNO and lung functions were measured respectively.FeNO and lung functions were analyzed on whether there were statistical differences between the subjects in these groups and whether their FeNO and lung functions were correlated. Results Comparison of FeNO and the percentages of the expected value(FEV1%) of forced expiratory volume in one second between acute exacerbation group [(58.79±12.25) ppb and(52.25±7.89)%], chronic persistent group [(42.13±11.38) ppb and(66.14±5.29)%], remission group[(25.41±7.15) ppb and(86.22±15.21)%] and the healthy control group[(12.84±6.22) ppb and(93.62±12.13)%], showed that FeNO in asthma acute exacerbation group, chronic persistent group and remission group was higher than that in the healthy control group, with statistically significant difference(all P 0.05), the differences in other groups were all statistically significant(all P<0.05). FeNO and FEV1% were negatively correlated at acute exacerbation(r=-0.779, P=0.000), but they were not correlated at chronic persistent and remission state. Conclusions FeNO values increased in asthma children.FeNO as a sensitive indicator to reflect airway inflammation can be used to evaluate the control and severity of airway inflammation.FeNO and FEV1% of lung functions were negatively correlated in asthma children at acute stage. Key words: Bronchial asthma; Exhaled nitric oxide; Lung function; Percentage of expected value of forced expiratory volume in one second