Exercise-induced bronchoconstriction in adolescent recreational athletes: Potential screening strategies.

Background: Intense physical exercise in athletes increases the risk to develop exercise-induced bronchocontriction (EIB). We aimed to study EIB prevalence and explore methods for effective EIB screening.

Methods: Three hundred twenty-seven adolescent athletes (12-18 years) performing at least 12 h of sports a week were included. The evaluation consisted of spirometry, eucapnic voluntary hyperpnoea test (EVH) to evaluate for EIB, FeNO, skin prick testing, blood sampling (serum markers of epithelial damage and mast cell activation), and questionnaires (AQUA^©, ACT, ACQ, and exposure and symptom-related questions).

Results: Of all athletes, 22% tested positive for EIB (n = 72), 14% reported a previous asthma diagnosis and 40% were atopic. Eighty percent of EIB⁺ athletes did not use any inhalation therapy. EIB⁺ athletes were significantly younger, had decreased FEV₁/FVC (%), and increased post-EVH-reversibility (%) post-salbutamol compared with EIB^- athletes. Furthermore, EIB was significantly associated with previous asthma diagnosis and atopy. The best predictors for a positive EVH test were AQUA^© score ≥ 6 (sensitivity of 78%, p = .0171) and wheezing during exercise (specificity of 82%, p = .0002). FeNO negatively and significantly correlated with maximal fall in FEV₁ post-EVH test in atopic athletes (r = -.2735, p = .0056). Maximal fall in FEV₁ was also associated with prior PM₁₀ exposure (p = .036). Serum markers of epithelial damage were significantly associated with training type, training intensity, EIB severity, and prior air pollution exposure.

Conclusion: Our findings support the effectiveness of a systematic respiratory screening approach, including baseline questionnaires, lung function tests, and FeNO measurement, to improve EIB detection in adolescent athletes in whom respiratory response to EVH testing is associated with prior exposure to air pollution.