system
Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, METHODS, RESULTS. Meshes: Bronchial Hyperreactivity, Bronchial Provocation Tests, Bronchoconstriction, Bronchoconstrictor Agents, Exercise Test, Female, Humans, Male, Methacholine Chloride, Military Personnel, Retrospective Studies, Young Adult.
user
Is methacholine challenge insufficient to exclude bronchial hyper-responsiveness in a symptomatic military population? Context: Bronchial hyper-responsiveness in a military population has been evaluated by direct and indirect challenge methods. We hypothesized that negative methacholine challenge testing (MCT) was not sufficient to exclude significant bronchial hyper-responsiveness in a symptomatic military population with exertional dyspnea. The purpose of our study was to identify bronchial hyper-responsiveness in symptomatic military recruits and active duty personnel with normal baseline spirometry and negative pharmacologic bronchoprovocation testing. We performed a retrospective single center electronic chart review of symptomatic service members with a negative MCT who completed a subsequent exercise challenge test (ECT). ECT was positive in 45 (26.4%) of 171 subjects (98 recruits). Subjects with a positive ECT had lower baseline forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC) and FEV1/FVC than those with a negative ECT, and these differences were statistically significant. The mean drop in FEV1 with exercise challenge positive patients was 17.9 ± 9.2%, and the mean drop in FEV1 with MCT was significantly greater in exercise challenge positive patients (-9.5 ± 5.5 vs. -7.6 ± 5.5, p = 0.042). Exercise-induced bronchoconstriction (EIB) was observed in 41% of all recruits who subsequently did not complete training. Only 1 recruit subject of 28 with EIB completed training.
assistant
Methacholine challenge is an insufficient screening test to detect bronchial hyper-responsiveness in a symptomatic military population. In military recruits, EIB is associated with training failure. Final Decision: yes