Objectives To evaluate, with a cardiopulmonary exercise test (CPET), the cardiopulmonary fitness of children with asthma, in comparison to healthy controls, and to identify the clinical and CPET parameters associated with the maximum oxygen uptake (VO2max) in childhood asthma.
Design This cross-sectional controlled study was carried out in CPET laboratories from two tertiary care paediatric centres. The predictors of VO2max were determined using a multivariable analysis.
Results A total of 446 children (144 in the asthma group and 302 healthy subjects) underwent a complete CPET. Mean VO2max was significantly lower in children with asthma than in controls (38.6±8.6 vs 43.5±7.5 mL/kg/min; absolute difference (abs. diff.) of −4.9 mL/kg/min; 95% CI of (−6.5 to −3.3) mL/kg/min; p<0.01) and represented 94%±9% and 107%±17% of predicted values, respectively (abs. diff. −13%; 95% CI (−17 to −9)%; p<0.01). The proportion of children with an impaired VO2max was four times higher in the asthma group (24% vs 6%, p<0.01). Impaired ventilatory efficiency with increased VE/VCO2 slope and low breathing reserve (BR) were more marked in the asthma group. The proportion of children with a decreased ventilatory anaerobic threshold (VAT), indicative of physical deconditioning, was three times higher in the asthma group (31% vs 11%, p<0.01). Impaired VO2max was associated with female gender, high body mass index (BMI), FEV1, low VAT and high BR.
Conclusion Cardiopulmonary fitness in children with asthma was moderately but significantly altered compared with healthy children. A decreased VO2max was associated with female gender, high BMI and the pulmonary function.
Trial registration number NCT04650464.
- child health
- respiratory medicine
Data availability statement
All data relevant to the study are included in the article or uploaded as supplementary information.
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.
JM and FS contributed equally.
Correction notice This article has been updated since it was first published. The surname of the ninth author has been corrected.
Contributors Study concept and design: JM, PA. Drafting of the manuscript: FS, JM, PA. Critical revision of the manuscript for important intellectual content: All. Statistical analysis: HH, M-CP. Obtained funding: PA. Guarantor: PA. All authors approved the final manuscript as submitted and agree to be accountable for all aspects of the work.
Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
Competing interests None declared.
Provenance and peer review Not commissioned; externally peer reviewed.
Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.