Are asthma-like symptoms in elite athletes associated with classical features of asthma?
- 1Respiratory and Allergy Research Unit, Department of Respiratory Medicine, Bispebjerg Hospital, Copenhagen University Hospital, Denmark
- 2Department of Respiratory and Sleep Medicine, Royal Prince Alfred Hospital, Camperdown, New South Wales, Australia
- Correspondence to Dr T K Lund, Respiratory and Allergy Research Unit, Department of Respiratory Medicine, Bispebjerg Hospital, Copenhagen University Hospital, 2400 Copenhagen NV, Denmark; tclund{at}dadlnet.dk
- Accepted 22 January 2009
- Published Online First 6 February 2009
Abstract
Background: Asthma is frequent in elite athletes and clinical studies in athletes have found increased airway inflammation.
Objective: To investigate asthma-like symptoms, airway inflammation, airway reactivity (AR) to mannitol and use of asthma medication in Danish elite athletes.
Methods: The study group consisted of 54 elite athletes (19 with doctor-diagnosed asthma), 22 non-athletes with doctor-diagnosed asthma (steroid naive for 4 weeks before the examination) and 35 non-athletes without asthma; all aged 18–35 years. Examinations (1 day): questionnaires, exhaled nitric oxide (eNO) in parts per billion, spirometry, skin prick test, AR to mannitol and blood samples. Induced sputum was done in subjects with asthma.
Results: No significant difference was found in values for eNO, AR and atopy between 42 elite athletes with and 12 without asthma-like symptoms. Elite athletes with doctor-diagnosed asthma had less AR (response dose ratio 0.02 (0.004) vs 0.08 (0.018) p<0.01) and fewer sputum eosinophils (0.8% (0–4.8) vs 6.0% (0–18.5), p<0.01) than non-athletes with doctor-diagnosed asthma. Use of inhaled corticosteroids was similar in the two groups (not significant). In all, 42 elite athletes had asthma-like symptoms but only 12 had evidence of current asthma. Elite athletes without asthma had asthma-like symptoms more frequently than non-athletes without asthma (68.6% vs 25.7%, p<0.001).
Conclusion: Asthma-like symptoms in elite athletes are not necessarily associated with classic features of asthma and alone should not give a diagnosis of asthma. More studies are needed to further investigate if and how the asthma phenotype of elite athletes differs from that of classical asthma.
Footnotes
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Funding Anti-Doping Denmark, Team Denmark, Research Foundation of Bispebjerg Hospital and the Beckett Foundation financially supported the study.
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Competing interests TKL has received financial support from GlaxoSmithKline. LP has received financial support from The Academy of Muscle Biology, Exercise and Health Research, The Health Insurance Foundation, Team Denmark and Anti-Doping Denmark. SDA is the inventor of the mannitol test, although it is owned by her employer the Sydney South West Area Health Service (SSWAHS). SDA owns shares in Pharmaxis Ltd that were purchased by the author in 2001. SDA does not own any options. SDA may benefit from royalties in the future. As an employee of SSWAHS, SDA acts as a consultant and invoices are issued by SSWAHS. AS has received mannitol test kits from Pharmaxis Ltd. VB has received financial support from Pharmaxis Ltd and the Danish Lung Association.
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Ethics approval The Danish National Committee on Biomedical Research Ethics approved this study.
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Provenance and Peer review Not commissioned; externally peer reviewed.
