Diagnosis of exercise-induced bronchoconstriction: eucapnic voluntary hyperpnoea challenges identify previously undiagnosed elite athletes with exercise-induced bronchoconstriction

BACKGROUND

There is increasing evidence to suggest many elite athletes fail to recognise and report symptoms of exercise-induced bronchoconstriction (EIB), supporting the contention that athletes should be screened routinely for EIB.

PURPOSE

To screen elite British athletes for EIB using eucapnic voluntary hyperpnoea (EVH).

METHODS

228 elite athletes provided written informed consent and completed an EVH challenge with maximal flow volume loops measured at baseline and 3, 5, 10 and 15 min following EVH. A fall of 10% in forced expiratory volume in 1 s (FEV(1)) from baseline was deemed positive. Two-way analysis of variance was conducted to compare FEV(1) at baseline and maximal change following EVH between EVH-positive and EVH-negative athletes who did and did not report a previous diagnosis of EIB. Significance was assumed if p ?0.05.

RESULTS

Following the EVH challenge 78 athletes (34%) demonstrated EVH positive. 57 out of the 78 (73%) athletes who demonstrated EVH positive did not have a previous diagnosis of EIB. 30 athletes reported a previous diagnosis of asthma, nine (30%) of whom demonstrated EVH negative. There was no significant difference between the magnitude of the fall in FEV(1) between athletes who reported a previous diagnosis of EIB and demonstrated EVH positive, and those with no previous diagnosis of EIB who demonstrated EVH positive (mean±SD; -21.6 ± 16.1% vs -17.1 ± 9.7%; p=0.07).

CONCLUSION

The high proportion of previously undiagnosed athletes who demonstrated EVH positive suggests that elite athletes should be screened routinely for EIB using a suitable bronchoprovocation challenge.