Exercise-Induced Bronchospasm: Diagnosis and Treatment

Exercise-induced bronchospasm (EIB) is acute and reversible airway narrowing that occurs during, and also frequently after, exercise. Because the presenting symptoms of EIB are nonspecific, objective evidence of bronchospasm should be documented to confirm a diagnosis. A 10% or greater decrease in the forced expiratory volume in 1 second (FEV1) from baseline after an adequate exercise challenge is accepted as diagnostic for EIB [1]. Adequate exercise challenges stimulate a significant increase in the ventilatory rate from baseline, which is necessary to trigger EIB in most patients. EIB occurs commonly in people with and without asthma. In people with a known history of asthma, exercise is one of the most common triggers of bronchospasm and affects 50% to 80% of asthmatics [2]. EIB occurs somewhat less commonly in those with allergic rhinitis or atopic disease but is still found in up to 40% of this cohort [3]. In the general population without asthma or atopy, the prevalence of EIB is approximately 10% [4]. The prevalence of EIB is even higher in elite athletes; reported prevalence rates in this group are as high as 50% [2]. Exercise-induced asthma and exercise-induced bronchospasm are 2 terms that are often used interchangeably This article has a companion CME exam that follows the article. To earn credit, read the article and complete the CME evaluation on pages 220 and 221. Estimated time to complete this activity is 1 hour. Faculty disclosure information appears on page 217.