Reported symptoms differentiate diagnoses in children with exercise-induced respiratory problems: findings from the Swiss Paediatric Airway Cohort (SPAC)

Abstract

Background: Exercise-induced breathing problems with similar clinical presentations can have different aetiologies. This makes distinguishing common diagnoses such as asthma, extrathoracic and thoracic dysfunctional breathing (DB), insufficient fitness, and chronic cough difficult. Objective: We studied which parent-reported, exercise-induced symptoms (EIS) can help distinguish diagnoses of EIS in children seen in respiratory outpatient clinics. Methods: This study was nested in the Swiss Paediatric Airway Cohort (SPAC), an observational study of children aged 0-17 years referred to paediatric respiratory outpatient clinics in Switzerland. We studied children aged 6-17 years and compared information on EIS from parent-completed questionnaires between children with different diagnoses. We used multinomial regression to analyse whether parent-reported symptoms differed between diagnoses (asthma as base). Results: Among 1109 children, EIS were reported for 732 (66%) (mean age 11 years, 318 of 732 [43%] female). Among the symptoms, dyspnoea 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 EIS 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. Localisation of dyspnoea (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. Conclusion: Parent-reported symptoms help distinguish different diagnoses in children with EIS. This highlights the importance of physicians obtaining detailed patient histories.

Reporting of paediatric exercise-induced respiratory symptoms by physicians and parents

“…Outpatient clinical letters usually included information related to specific symptom(s) and bronchodilator use, but less often provided important additional details such as perceived symptom localisation, respiratory phase, and timing of onset of EIS. These characteristics of EIS have been described as important factors for differentiating dysfunctional breathing from asthma and other aetiologies (3,11,(25)(26)(27), however this information was documented in the outpatient clinical letter in less than half of the children.…”

“…The EIS domains -such as timing of onset, severity, perceived localisation, relation to exercise intensity and duration, and response to treatment are important features in the clinical history. Exercise-induced wheeze, cough, and chest tightness are common in asthma (10,11), while stridor and dyspnoea are more often noted for extrathoracic dysfunctional breathing (9,11).…”