Small Airway Dysfunction Measured by Impulse Oscillometry and Fractional Exhaled Nitric Oxide Is Associated With Asthma Control in Children

Liang-Mei Lin; Yu-Jun Chang; Kuender D Yang; Ching-Hsiung Lin; Jien-Wen Chien; Jun-Kai Kao; Ming-Sheng Lee; Tsay-I Chiang; Ching-Yuang Lin; Yi-Giien Tsai

doi:10.3389/fped.2022.877681

Small Airway Dysfunction Measured by Impulse Oscillometry and Fractional Exhaled Nitric Oxide Is Associated With Asthma Control in Children

Front Pediatr. 2022 Jun 17:10:877681. doi: 10.3389/fped.2022.877681. eCollection 2022.

Authors

Liang-Mei Lin¹, Yu-Jun Chang², Kuender D Yang^{3

4}, Ching-Hsiung Lin^{5

6

7

8}, Jien-Wen Chien^{9

10}, Jun-Kai Kao^{9

10

11

12

13}, Ming-Sheng Lee⁹, Tsay-I Chiang¹⁴, Ching-Yuang Lin¹⁵, Yi-Giien Tsai^{9

10

13

16}

Affiliations

¹ Respiratory Therapy Section for Children, Changhua Christian Children's Hospital, Changhua, Taiwan.
² Epidemiology and Biostatistics Center and Big Data Center, Changhua Christian Hospital, Changhua, Taiwan.
³ Departments of Pediatrics, Mackay Memorial Hospital, Taipei City, Taiwan.
⁴ Department of Microbiology and Immunology, National Defense Medical Center, Taipei City, Taiwan.
⁵ Division of Chest Medicine, Department of Internal Medicine, Changhua Christian Hospital, Changhua, Taiwan.
⁶ Institute of Genomics and Bioinformatics, National Chung Hsing University, Taichung, Taiwan.
⁷ Ph.D. Program in Translational Medicine, National Chung Hsing University, Taichung, Taiwan.
⁸ Department of Recreation and Holistic Wellness, MingDao University, Changhua, Taiwan.
⁹ Department of Pediatrics, Changhua Christian Children's Hospital, Changhua, Taiwan.
¹⁰ Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan.
¹¹ Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan.
¹² Frontier Molecular Medical Research Center in Children, Changhua Christian Children Hospital, Changhua, Taiwan.
¹³ School of Medicine, Kaohsiung Medical University, Taichung, Taiwan.
¹⁴ College of Nursing, Hungkuang University, Taichung, Taiwan.
¹⁵ Division of Pediatric Nephrology, Children's Hospital, China Medical University, Taichung, Taiwan.
¹⁶ School of Medicine, Chung Shan Medical University, Taichung, Taiwan.

Abstract

Background: Impulse oscillometry (IOS) and fractional exhaled nitric oxide (FeNO) are sensitive and non-invasive methods to measure airway resistance and inflammation, although there are limited population-based studies using IOS and FeNO to predict asthma control.

Objective: This study aimed to investigate the utility of IOS and FeNO for assessing childhood asthma control in terms of small airway dysfunction and airway inflammation.

Methods: This prospective observational cohort study enrolled 5,018 school children (aged 6-12 years), including 560 asthmatic children and 140 normal participants. FeNO, spirometry, IOS, bronchial dilation test, total IgE, and childhood asthma control test (C-ACT) were measured. FeNO, IOS, spirometry, and C-ACT results were correlated with childhood asthma with and without control.

Results: Uncontrolled asthmatic children had abnormal FeNO, IOS, and spirometric values compared with control subjects (P < 0.05). IOS parameters with R5, R5-R20, X5, Ax, △R5, and FeNO can predict lower C-ACT scales by the areas under receiver operating characteristic curves (AUCs) (0.616, 0.625, 0.609, 0.622, 0.625, and 0.714). A combination of FeNO (>20 ppb) with IOS measure significantly increased the specificity for predicting uncontrolled asthma patients compared with FeNO alone (P < 0.01). A multiple regression model showed that small airway parameter (R5-R20) was the strongest risk factor [OR (95% CI): 87.26 (7.67-993.31)] for uncontrolled asthma patients. Poor control with lower C-ACT scales correlated with high FeNO (r = -0.394), R5 (r = -0.106), and R5-R20 (r = -0.129) in asthmatic children (P < 0.05).

Conclusion: A combined use of FeNO and IOS measurements strongly predicts childhood asthma with or without control.

Keywords: allergic asthma; asthma control; fractional exhaled nitric oxide; impulse oscillometry; pulmonary function.