Association of longitudinal fractional exhaled nitric oxide measurements with asthma control in atopic children

• Published in: Respiratory medicine Vol. 109; no. 5; pp. 572 - 579
• Main Authors: Yang, Sohyoung, Park, Joohyun, Lee, Youn Kyung, Kim, Heon, Hahn, Youn-Soo
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.05.2015; Elsevier Limited
• Subjects: Adolescent; Asthma; Asthma - drug therapy; Asthma - metabolism; Asthma - physiopathology; Child; Disease management; Exhalation - physiology; Female; Follow-Up Studies; Forced Expiratory Volume - physiology; Fractional exhaled nitric oxide; Humans; Investigations; Logistic Models; Longitudinal Studies; Loss of asthma control; Lung function; Male; Nitric Oxide - metabolism; Pulmonary/Respiratory; Respiratory Function Tests; ROC Curve; Spirometry; Lung function; Fractional exhaled nitric oxide; Loss of asthma control; Child; Asthma
• ISSN: 0954-6111; 1532-3064
• DOI: 10.1016/j.rmed.2015.03.003

Summary Objectives We sought to determine whether longitudinal measurements of FeNO are informative for future loss of asthma control in children with atopic asthma. Methods One hundred seventy-eight patients aged 8–16 years with atopic asthma were enrolled. FeNO and lung functions were serially monitored 10 times or more over 2 years when subjects were not receiving controller medications. After completion of monitoring, 1-year observation on the occurrence of loss of asthma control was performed and associations of loss of asthma control with spirometric and FeNO measurements were analyzed. Results Loss of asthma control occurred during observation periods in 110 (76%) of 145 patients who completed the study. Of all monitored parameters including airway reactivity, the highest FeNO of serial measurements (H-FeNO) (adjusted odds ratio (aOR), 1.21; 95% CI, 1.08–1.36) and the rate of FeNO levels higher than 21 ppb (R21 FeNO) (aOR, 1.06; 95% CI, 1.01–1.11) were the only independent predictors of upcoming control loss in the multiple logistic regression analysis. In receiver-operator characteristic curve analysis, H-FeNO > 37 ppb and R21 FeNO > 20% demonstrated 91% and 88% sensitivity for a future loss of asthma control at the cost of low specificity (60% and 65%, respectively). In contrast, H-FeNO > 47 ppb and R21 FeNO > 41% gave 96% and 88% specificity, but these sacrificed sensitivity to 70% and 72%, respectively. Conclusions Our data show that both amount and frequency of a FeNO increase during longitudinal monitoring are helpful in predicting asthma control status.