Background: Ventilatory parameters obtained during exercise predict survival in several chronic diseases; however, long-term changes in exercise ventilatory parameters in patients with cystic fibrosis (CF) have yet to be examined and potential differences between sexes in CF are unknown.
Purpose: We sought to examine the change in exercise ventilatory parameters over time in patients with CF and determine if the change is different between sexes.
Methods: Exercise capacity (VO2 peak) and exercise ventilatory parameters (VE/VO2 peak, VE/VCO2 peak, and VE/VCO2 slope) were determined from a maximal cardio-pulmonary test on a cycle ergometer on two visits separated by 39 ± 16 months in 20 patients with CF (10 female, 10 male).
Results: No differences between sexes were observed at visit 1 (all p > 0.05). Overall, exercise ventilatory parameters significantly (p < 0.05) deteriorated between visits, with no change (p > 0.05) in VO2 peak. Moreover, compared to males, female patients exhibited greater deteriorations in VE/VO2 peak (p = 0.001), VE/VCO2 peak (p = 0.002), and VE/VCO2 slope (p = 0.016) between visits.
Conclusions: These data in patients with CF indicate that exercise ventilatory parameters decline over time despite no change in VO2 peak, and female patients exhibit a more rapid deterioration compared to males.
Keywords: Exercise capacity; Pulmonary function; Ventilatory efficiency.