Exercise in elite summer athletes: Challenges for diagnosis

Area of Science:

• Sports Medicine
• Respiratory Medicine
• Exercise Physiology

Background:

• Elite athletes exhibit high rates of asthma and exercise-induced bronchoconstriction (EIB).
• Sporting bodies increasingly require objective measurements for asthma/EIB diagnosis to permit beta-agonist use.
• Bronchial provocation tests like methacholine and eucapnic voluntary hyperpnea (EVH) are potential objective measures.

Purpose of the Study:

• To examine the relationship between asthma symptoms and responses to methacholine and EVH challenges in elite summer-sport athletes.
• To guide practitioners on objective methods for identifying asthma and EIB in athletes.

Main Methods:

• Fifty elite summer-sport athletes (with or without asthma) were recruited.
• Subjects completed a respiratory questionnaire.
• Bronchoprovocation testing with methacholine and EVH was performed on separate days.

Main Results:

• 42 athletes reported respiratory symptoms; 9 had positive methacholine tests (mean PD(20) 1.69 ± 2.05 µmol).
• 25 athletes had positive EVH tests (mean FEV(1) fall 25.4% ± 15%).
• All positive methacholine responders were positive on EVH, but methacholine had 61% NPV and 36% sensitivity for EVH responsiveness.

Conclusions:

• The pathogenesis of EIB in elite athletes may differ from asthma.
• Neither respiratory symptoms nor methacholine challenge alone are sufficient for diagnosing EIB in this population.
• EVH appears to be a more suitable objective measure for identifying EIB in elite athletes.