Résumé
Objective: compare the aerobic physical capacity between children with cystic fibrosis and healthy children during a cardiorespiratory exercise test, and identify predictive factors of maximal oxygen consumption (VO2max) in children with cystic fibrosis.Materials and method: this controlled cross-sectional study was carried out at a functional exploration center within the Montpellier’s University Hospital Center, involving children from 7 to 17. VO2max of each child was measured during a cardiorespiratory exercise test. Multivariate analysis was employed to identify factors associated with VO2max.Results: a total of 345 children were included in the study, with 56 in the cystic fibrosis group and 289 in the control group. The mean VO2max was significantly lower in the cystic fibrosis group (39.64±9.22 mL/kg/min versus 43.42±7.63 mL/kg/min, representing 98.44%±19.48% versus 106.72%±16.65% of predicted values, respectively (p<0.01). The proportion of children with impaired VO2max was approximately three times higher in the cystic fibrosis group than in the control group (20% versus 7%, respectively (p<0.01)). Six factors were associated with impaired VO2max, including a higher age, a higher Body Mass Index (BMI), the female gender, a lower forced expiratory volume in one second (FEV1), a higher breathing reserve and a lower maximal oxygen pulse.Conclusion: in the cystic fibrosis group, the VO2max levels were overall good, but statistically lower compared to the control population. An impaired VO2max was found to be associated with a higher age, a higher BMI, the female gender, a lower FEV1, a higher breathing reserve and a lower maximal oxygen pulse.