Incidence of exercise-induced asthma in high school population in British Columbia

The Free Running Asthma Screening Test (FRAST) was performed on 830 randomly selected volunteers (age 14-17) chosen from British Columbia school students. An educational workshop on asthma was presented before testing. A self-reported questionnaire was distributed to evaluate predisposing factors. Air quality parameters were obtained on days of testing. FRAST was used to challenge exercise induced asthma (EIA). Peak expiratory flow rate (PEFR) was used to obtain baseline and post exercise spirometry. A 15% decrease in PEFR was considered a positive challenge result. Of 830 subjects tested, 110 (13.2%) responded positively to exercise challenge. Of the population tested, 21.8% self-reported a history of allergic disease, 76.4% of whom were from the positive responders' group. From the positive group only 72 (65.4%) were previously diagnosed as asthmatic. History of allergic disease was the strongest predisposing factor. The results indicate that inexpensive screening may improve early diagnosis and thus better preventive management.