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 (nondyspnea 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 nondyspnea group. Positive CLE tests: 5 of 34 in the dyspnea group and three of 41 in the nondyspnea group. The estimated prevalence of EIB was 23.1% (95% confidence interval [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 nondyspnea 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.