Effect of inhaled corticosteroids on bronchial asthma in Japanese athletes.

BACKGROUND Asthma has a higher prevalence in athlete populations such as Olympic athletes than in the general population. Correct diagnosis and management of asthma in athletes is important for symptom control and avoidance of doping accusations. However, few reports are available on asthma treatment in the athlete population in clinical practice. In this study, we focused on the clinical efficacy of inhaled corticosteroid (ICS) for asthma in a Japanese athlete population. METHODS The study subjects included athletes who visited the Niigata Institute for Health and Sports Medicine, Niigata, Japan for athletic tests and who were diagnosed with asthma on the basis of respiratory symptoms and positive results in a bronchodilator or bronchial provocation test such as exercise, hypertonic saline, or methacholine provocation. The athletes received ICS alone for at least 3 months, and the clinical background, sports type, and treatment efficacy were analyzed. RESULTS The study population comprised 80 athletes (59 men and 21 women) with a median age of 16.0 years. Regarding sports type, 28 athletes engaged in winter sports (35%), 22 in endurance sports (27.5%), and 25 in indoor sports (31.3%). Although ICS is the primary treatment in athlete asthma, 16.3% of the athletes showed an unsatisfactory response to treatment according to the Global Evaluation of Treatment Effectiveness (GETE). These subjects were characterized by a decreased response to methacholine and lower values for FEV1/FVC and type 2 helper T cell (Th2)-associated biomarkers relative to responsive athletes. In multivariate analysis, FEV1/FVC and the logarithm to the base 10 of the IgE level were independently associated with the ICS response. CONCLUSIONS These data suggest that ICS is effective for asthma in most athletes. However, certain asthmatic athletes are less responsive to ICS than expected. The pathogenesis in these subjects may differ from that of conventional asthma characterized by chronic allergic airway inflammation.