title: The prevalence of airways hyperresponsiveness in members of an exercise training facility.
abstract: Athletes have a high prevalence (11-50%) of exercise-induced asthma, which may be caused by the hyperventilation accompanying repetitive bouts of strenuous exercise. We hypothesized that recreational exercisers would display a similar trend. Eucapnic voluntary hyperventilation (EVH) bronchoprovocation (breathing 21% O2, 5% CO2, and 74% N2 at 60% of MVV for 5 minutes) was performed to determine the prevalence of airways hyperresponsiveness (AHR) in adults (n=212, 146 males, mean +/- standard deviation, age 32 +/- 10 years) who exercised regularly (10 +/- 10 years, 31 +/- 28% of their lives): none had a previous diagnosis of asthma. AHR was defined by at least a 10%, 20%, or 25% decline in FEV1, FEF(25-75), or PEFR, respectively, by spirometry at 1, 5, 10, and 15 minutes post-EVH. Forty-one of 212 (19%) tested positive for AHR: 20 of 41 (49%) were positive by FEV1, 28 of 41 (68%) by FEF(25-75), and 27 of 41 (66%) by PEFR. Comparing responders with nonresponders: pre-EVH lung function was equivalent, except for FEV1, which was reduced (p<0.05) in responders (96 +/- 13 vs. 102 +/- 12% predicted). Mean maximal negative deflections for responders were: for FEV1, -17 +/- 7%; FEF(25-75), -31 +/- 10%; PEFR, -38 +/- 11%. Ranges of decline for responders were: FEV1, -10 to -33%; FEF(25-75), -20 to -59%; PEFR, -25- to -70%. We conclude that in these regular exercisers, the prevalence of AHR is high and comparable with some athletic populations.
authors.affiliation: Division of Pulmonary, Allergy, Critical Care and Occupational Medicine, Department of Medicine, School of Medicine, Indiana University, Indianapolis, Indiana, USA. emannix@iupui.edu
authors.forename: Edward T
authors.initials: ET
authors.lastname: Mannix
authors.forename: Melanie
authors.initials: M
authors.lastname: Roberts
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Fagin
authors.forename: Brandie
authors.initials: B
authors.lastname: Reid
authors.forename: Mark O
authors.initials: MO
authors.lastname: Farber
mesh_terms: D000328:Adult; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D012129:Respiratory Function Tests; D012130:Respiratory Hypersensitivity / Q000453:epidemiology* / Q000209:etiology