title: Reproducibility of the bronchoconstrictive response to eucapnic voluntary hyperpnoea.
abstract: BACKGROUND
  Eucapnic voluntary hyperpnoea (EVH) is considered an effective bronchoprovocation challenge for identifying exercise-induced bronchoconstriction (EIB). However, the reproducibility of the hyperpnoea-induced bronchoconstriction (HIB) response elicited by EVH remains unknown and was therefore the focus of this study.
  
  
  METHODS
  Two cohorts of 16 physically active males (each cohort comprised 8 controls and 8 with physician diagnosis of asthma) participated in two studies of the short- and long-term reproducibility of the bronchoconstrictive response to an EVH test with dry air. EVH was performed on days 0, 7, 14, and 21 (short-term study), and 0, 35, and 70 (long-term study). HIB was diagnosed by a ≥10% fall in forced expiratory volume in 1 s (FEV1) after EVH.
  
  
  RESULTS
  On day 0 of the short-term study, FEV1 fell by 2 ± 1% (P < 0.05) and 27 ± 18% (P < 0.01) from pre-to post-EVH in control and HIB-positive groups respectively. The post-EVH fall in FEV1 did not differ across the short-term study test days. In the HIB-positive group, the day-to-day coefficient of variation, reproducibility, and smallest meaningful change for the fall in FEV1 were 12%, 328 mL, and 164 mL, respectively. On day 0 of the long-term study, FEV1 fell by 2 ± 2% and 25 ± 18% (P < 0.01) after EVH in control and HIB-positive groups respectively. The post-EVH fall in FEV1 did not differ across the long-term study test days. In the HIB-positive group, the day-to-day coefficient of variation, reproducibility, and smallest meaningful change for the fall in FEV1 were 10%, 196 mL, and 98 mL respectively.
  
  
  CONCLUSIONS
  The EVH test elicits a reproducible bronchoconstrictive response in physically active males with physician diagnosed asthma. These data thus support the clinical utility of the EVH test for EIB screening and monitoring.
authors: Sport, Health and Performance Enhancement (SHAPE) Research Group, School of Science and Technology, Nottingham Trent University, Nottingham, NG11 8NS, UK. Electronic address: Neil.williams@ntu.ac.uk.
authors: N C
authors: NC
authors: Williams
authors: Sport, Health and Performance Enhancement (SHAPE) Research Group, School of Science and Technology, Nottingham Trent University, Nottingham, NG11 8NS, UK. Electronic address: Michael.johnson@ntu.ac.uk.
authors: M A
authors: MA
authors: Johnson
authors: Sport, Health and Performance Enhancement (SHAPE) Research Group, School of Science and Technology, Nottingham Trent University, Nottingham, NG11 8NS, UK. Electronic address: Kirsty.hunter@ntu.ac.uk.
authors: K A
authors: KA
authors: Hunter
authors: Sport, Health and Performance Enhancement (SHAPE) Research Group, School of Science and Technology, Nottingham Trent University, Nottingham, NG11 8NS, UK. Electronic address: Graham.sharpe@ntu.ac.uk.
authors: G R
authors: GR
authors: Sharpe
mesh_terms: D000328:Adult; D001249:Asthma / Q000175:diagnosis* / Q000503:physiopathology; D001250:Asthma, Exercise-Induced / Q000175:diagnosis* / Q000503:physiopathology; D016084:Bronchoconstriction / Q000502:physiology*; D016022:Case-Control Studies; D015331:Cohort Studies; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D006985:Hyperventilation / Q000503:physiopathology; D008297:Male; D008451:Maximal Voluntary Ventilation; D015203:Reproducibility of Results; D014797:Vital Capacity / Q000502:physiology
keywords: Asthma; Eucapnic voluntary hyperpnoea; Exercise-induced bronchoconstriction; Reproducibility