Objective: To determine the accuracy of clinically diagnosed exercise-induced bronchospasm (EIB) and asthma among National Collegiate Athletic Association Division I student athletes.
Design: Cohort study.
Setting: Division I university athletic department and primary care sports medicine clinic/athletic training room.
Patients: All varsity athletes were eligible for the study. Seventy-five participants entered the study; 74 completed all the study protocols.
Interventions: Study participants underwent measurement of exhaled nitric oxide (eNO), followed by baseline spirometry. Eucapnic voluntary hyperventilation (EVH) was then performed, followed by spirometry every 3 minutes for a total of 21 minutes to measure change in forced expiratory volume in 1 second.
Main outcome measures: Exhaled nitric oxide levels, baseline spirometry, and response of forced expiratory volume in 1 second to EVH.
Results: There were a total of 16 subjects with a positive EVH test. There were 16 (80%) individuals using a bronchodilator who had a negative EVH test versus 4 (20%) who had a positive test. Mean eNO values were different across subject groups defined by treatment status, although not statistically significant. The highest mean eNO value of 24.32 ppb was found in subjects only taking bronchodilators compared with the lowest mean value of 16.75 ppb in athletes who were not taking any medications.
Conclusions: The results from this study provide further evidence to support the need for objective testing to correctly diagnose EIB. These data suggest that measuring eNO may help to distinguish truly isolated EIB from asthma in athletes, but a larger study is needed to confirm these initial observations.