A comparison of two challenge tests for identifying exercise-induced bronchospasm in figure skaters.

OBJECTIVES Studies documenting the increased incidence of exercise-induced bronchospasm (EIB) in figure skaters have employed a method that incorporates on-ice exercise with rink-side spirometry. The literature suggests that bronchial provocation challenge testing is better than exercise testing for identifying EIB. To test this hypothesis in figure skaters, a unique athletic population that trains and competes in cold air, we compared these two methods in the same individuals. PATIENTS/METHODS Two challenge tests were performed on a group of competitive figure skaters (n = 29, 26 female subjects; mean+/-SD age = 12.3+/-3.5 years): (1) rink-side (temperature = 14 degrees C, humidity = 60%) spirometry before and 1, 5, 10, and 15 min after 5 min of intense skating; and (2) eucapnic voluntary hyperventilation (EVH), breathing 5% CO2, 21% O2, balance N2 at a rate of 60% of maximum voluntary ventilation (not to exceed 70 L/min) for 5 min (temperature = 18 degrees C, humidity = 50%), with an identical pretest and posttest spirometry schedule. EIB was defined as at least one of the following: a > or =10% decline in Fev1; a > or = 20% decline in maximum midexpiratory flow rate; or a > or = 25% decline in peak expiratory flow rate. RESULTS Sixteen of 29 skaters (55%) developed EIB: 9 were positive by on-ice testing; 12 were positive by EVH testing; 5 were positive on both tests; on-ice testing missed 7 skaters with EIB; EVH testing missed 4 with EIB. CONCLUSION In the group of figure skaters studied, EVH challenge testing was better at identifying EIB than on-ice exercise testing. However, these data suggest that evaluation for EIB in athletes who train and compete in the cold should include exercise testing in cold air along with a challenge test such as EVH to increase the yield of positive responders.