title: Are asthma-like symptoms in elite athletes associated with classical features of asthma?
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).
  
  
  CONCLUSIONS
  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.
authors.affiliation: Respiratory and Allergy Research Unit, Department of Respiratory Medicine, Bispebjerg Hospital, Copenhagen University Hospital, 2400 Copenhagen NV, Denmark. tclund@dadlnet.dk
authors.forename: T K
authors.initials: TK
authors.lastname: Lund
authors.forename: L
authors.initials: L
authors.lastname: Pedersen
authors.forename: S D
authors.initials: SD
authors.lastname: Anderson
authors.forename: A
authors.initials: A
authors.lastname: Sverrild
authors.forename: V
authors.initials: V
authors.lastname: Backer
mesh_terms: D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D001944:Breath Tests; D001980:Bronchi / Q000187:drug effects; D001985:Bronchial Provocation Tests; D001993:Bronchodilator Agents / Q000494:pharmacology; D003430:Cross-Sectional Studies; D003718:Denmark / Q000453:epidemiology; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D008297:Male; D008353:Mannitol / Q000494:pharmacology; D009569:Nitric Oxide / Q000032:analysis; D013177:Sports / Q000706:statistics & numerical data*; D013183:Sputum / Q000166:cytology; D014797:Vital Capacity / Q000502:physiology; D055815:Young Adult
chemical_list: D001993:Bronchodilator Agents; D009569:Nitric Oxide; D008353:Mannitol