Exercise-induced breathing problems with similar clinical presentations can have different etiologies. This makes distinguishing common diagnoses such as asthma, extrathoracic and thoracic dysfunctional breathing (DB), insufficient fitness, and chronic cough difficult.
We studied which parent-reported, exercise-induced symptoms can help distinguish diagnoses in children seen in respiratory outpatient clinics.
This study was nested in the Swiss Paediatric Airway Cohort (SPAC), an observational study of children aged 0-17 years referred to pediatric respiratory outpatient clinics in Switzerland. We studied children aged 6-17 years and compared information on exercise-induced symptoms from parent-completed questionnaires between children with different diagnoses. We used multinomial regression to analyze whether parent-reported symptoms differed between diagnoses (asthma as base).
Among 1109 children, exercise-induced symptoms were reported for 732 (66%) (mean age 11 years, 318 of 732 [43%] female). Among the symptoms, dyspnea best distinguished thoracic DB (relative risk ratio [RRR] 5.4, 95%CI 1.3-22) from asthma. Among exercise triggers, swimming best distinguished thoracic DB (RRR 2.4, 95%CI 1.3-6.2) and asthma plus DB (RRR 1.8, 95%CI 0.9-3.4) from asthma only. Late onset of symptoms was less common for extrathoracic DB (RRR 0.1, 95%CI 0.03-0.5) and thoracic DB (RRR 0.4, 95%CI 0.1-1.2) compared with asthma. Localization of dyspnea (throat vs. chest) differed between extrathoracic DB (RRR 2.3, 95%CI 0.9-5.8) and asthma. Reported respiration phase (inspiration or expiration) did not help distinguish diagnoses.
Parent-reported symptoms help distinguish different diagnoses in children with exercise-induced symptoms. This highlights the importance of physicians obtaining detailed patient histories.

Copyright © 2020. Published by Elsevier Inc.

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