A Longitudinal Study of a Selected Pediatric Asthmatic Population with Normal and Abnormal Spirometry at Baseline: An Emphasis on Treatment Outcomes

Abstract

Sornsiri Yimlamai, Kanokpan Ruangnapa, Wanaporn Anuntaseree, Kantara Saelim, Pharsai Prasertsan, Kantisa Sirianansopa Department of Pediatrics, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla, 90110, ThailandCorrespondence: Kanokpan Ruangnapa, Department of Pediatrics, Faculty of Medicine, Prince of Songkla University, Hat-Yai, Songkhla, 90110, Thailand, Tel [phone], Fax [phone], Email [email protected]: It is still unclear whether considering abnormal spirometry as a marker for disease control can help physicians adjust asthma controllers in children because of the scarcity of pediatric studies. We aimed to investigate the prevalence of abnormal spirometry in a selected pediatric asthmatic population and its effect on longitudinal outcomes.Patients and Methods: This retrospective cohort study was conducted at the Songklanagarind Hospital, Thailand. Children with asthma aged < 18 years were recruited for review if they attended the clinic and underwent acceptable spirometry with bronchodilator responsiveness (BDR) tests after receiving asthma treatment for at least 3 months between January 2011 and June 2022. Differences in baseline characteristics, atopic factors, asthma treatment, and outcomes were analyzed between the normal and abnormal spirometry groups over a 12-month post-spirometry period.Results: The mean age of the 203 enrolled patients was 10.9 ± 2.6 years. Abnormal spirometry, defined as airflow limitation or the presence of BDR, was observed in 58.1% of patients. No significant differences were observed in baseline characteristics, atopic factors, asthma treatment, or outcomes between the normal and abnormal spirometry groups. Further analysis of 107 patients with abnormal spirometry with symptom control revealed that physicians adjusted the asthma controller based on spirometry and symptoms in 84 and 23 patients, respectively. There was no significant difference in the loss of disease control over the 12-month post-spirometry period between the two groups.Conclusion: Abnormal spirometry was found in 58.1% of treated school-aged patients with asthma. Abnormal spirometry results were not associated with poor asthma outcomes during the 12-month follow-up. Both symptom-based and spirometry-based adjustments of asthma controllers resulted in comparable symptom control over a 12-month follow-up period in the selected population.Keywords: pulmonary function test, lung function test, childhood asthma, bronchodilator responsiveness

Keywords

• pulmonary function test
• lung function test
• childhood asthma
• bronchodilator responsiveness