Effectiveness of Ipratropium Bromide in Preventing Exercise-induced Bronchoconstriction in Athletes (STAMINA)

Exercise-induced asthma (EIA) is common and often unrecognized among endurance athletes. The mechanisms of asthma appear to be different between athletes and non-athletes, in that the occurrence of asthma is higher among endurance athletes and seems to be promoted by training. This suggests that factors inherent to athleticism, such as the parasympathetic nervous system, which has been shown to change with endurance training and is known to lead to narrowing of the airways, may be involved with the development of asthma in athletes. Although asthma mechanisms and treatments have been extensively studied in classic asthmatics, there is very limited data in athletes.

This will be a double-blind placebo-controlled study in which we plan to study 40 competitive endurance athletes. We will conduct an exercise test to evaluate maximal oxygen uptake and 2 exercise challenge tests to provoke EIA. Prior to the exercise challenge tests the athletes will randomly receive inhaled placebo or inhaled ipratropium bromide. We will compare the athletes' airway response to the exercise challenge with and without the active drug. We will also obtain a blood sample from all athletes to test for allergies and evaluate whether our results are affected by atopic predisposition.

If ipratropium bromide proves to prevent EIA in athletes, this drug may be more appropriate and effective than the currently used beta-2 agonists to target EIA in this population. The results of this study may lead to improved clinical management of athletes with asthma.