Prevalence of exercise-induced bronchoconstriction and laryngeal obstruction in adolescent athletes

OBJECTIVES: To study the prevalence of exercise-induced bronchoconstriction (EIB) and exercise-induced laryngeal obstruction (EILO) in adolescent athletes. METHODS: All adolescents (n = 549) attending first year at a sports high school in 2016 and 2017, were invited to answer a questionnaire on respiratory symptoms. The 367 responding participants were divided into two groups based on whether they reported exercise-induced dyspnea (dyspnea group) or not (non-dyspnea group). Randomly selected participants in each group were invited to undergo two standardized exercise tests, an EIB test and a continuous laryngoscopy exercise (CLE) test, to investigate EILO. RESULTS: In total, 98 participants completed an EIB test, 75 of whom also completed a CLE test. Positive EIB tests: eight of 41 in the dyspnea group and 16 of 57 in the non-dyspnea group. Positive CLE tests: five of 34 in the dyspnea group and three of 41 in the non-dyspnea group. The estimated prevalence of EIB was 23.1 % (95 % CI 14.5 - 33.8) and of EILO 8.1 % (95 % CI 2.5 - 18.5) in the whole study population. No differences in prevalence of EIB or EILO were found between the dyspnea and the non-dyspnea groups. CONCLUSION: EIB was highly prevalent in this cohort of adolescent athletes. EILO was less prevalent, but represents an important differential diagnosis to EIB. Self-reported exercise-induced dyspnea is a weak indicator for both EIB and EILO and standardized testing should be provided.