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

This is the authors' abstract. We don't add key points for this paper.

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. Highlights box What is already known about this topic? Experts suggest that information about the symptoms and their onset and duration can assist accurate diagnosis of children with exercise-induced respiratory problems, but no original studies have tested this. (29/35 words) What does this article add to our knowledge? Exercise-induced symptoms reported by parents and further information about their onset, triggers, and effects of treatment help differentiate diagnoses in children with exercise-induced respiratory problems. (25/35 words) How does this study impact current management guidelines? Our results emphasize the importance of taking detailed symptom histories of children with exercise-induced problems, and suggest which questions are most helpful.