Abstract

Exercise-induced asthma (EIA) is a clinical syndrome characterized by transient airflow obstruction typically 5-15 min after cessation of physcial exertion. Approximately 40-50 of those with asthma exhibit a refractory period, i.e., diminished bronchoconstriction to exercise performed within 2 h. The pathophysiology of EIA is related to thermal events within the intrathoracic airways. Alterations in the temperature of the airways and/or osmolarity in the epithelial lining fluid cause release of mediators in the airways and the development of bronchoconstriction. Measurement of lung function is an important first diagnostic test. It there is no evidence of airflow obstruction at rest, then either bronchoprovocation testing or exercise challenge testing is indicated. Nonpharmacologic therapy includes warm-up exercise prior to training or competition to induce a refractory period and to prevent/reduce bronchoconstriction. An inhaled beta-2-adrenergic agonist, e.g., albuterol, is usually effective for preventing/treating EIA. Cromoly sodium is an alternative class of medication that inhibits both the early and late phase responses. Health care providers should encourage individuals with asthma to be physically active and should provide education about asthma management as related to EIA. Verf.-Referat