title: Spirometry in children with asthma and/or allergic rhinitis: comparison of FEF25-75% with the standard measures.
abstract: BACKGROUND
  Forced expiratory flow between 25% and 75% of vital capacity (FEF25-75%), a spirometric measure of small airways, may predict the presence of airway responsiveness both in asthmatics and in allergic rhinitis (AR). We aimed to search the correlation between FEF25-75% and standard measures of spirometry (forced expiratory volume in the first second [FEV1%] and FEV1/FVC [forced vital capacity]) in different clinical conditions, that is in children with asthma, in children with asthma and AR, in children with AR and in healthy children.
  
  
  METHODS
  Children with asthma (N.=116), asthma plus AR (N.=25), AR (N.=75) and healthy controls (N.=52) were evaluated. Clinical examinations, spirometry and bronchodilation tests were performed.
  
  
  RESULTS
  In asthmatics there was a strong correlation between FEF25-75% and FEV1% (r=0.596, P<0.001); and between FEF25-75% and FEV1/FVC (r=0.740, P<0.001). In AR patients correlation between FEF25-75% and FEV1% (r=0.367, P=0.001); and between FEF25-75% and FEV1/FVC (r=0.534, P<0.001) were less prominent compared to asthmatics but they were still significant and strong. In children with both AR and asthma correlation between FEF25-75% and FEV1% (r=0.633, P=0.001) and between FEF25-75% and FEV1/FVC (r=0.539, P=0.005) were again significant. Pre-test FEV1% and FEF25-75% in AR patients were lower than that of the control subjects. After the bronchodilation, percentage change in the FEV1 in AR patients were significantly higher than the control subjects (P=0.010). AR patients showed significant increases in FEV1%, (P<0.001), FEF25-75%, (P<0.001) and (P=0.001) after the bronchodilation test. Within the AR patients, only 12/75 (16.0%) showed bronchodilation with salbutamol. Among the ones with a FEF25-75% <65%, FEV1% was normal in 6/43 (14%) patients in asthmatics, and FEV1% was normal in 3/9 (33%) patients in asthma +AR patients.
  
  
  CONCLUSIONS
  Besides the FEV1% and FEV1/FVC, the FEF25-75% may be a useful and early spirometric parameter to evaluate the children with asthma and or AR.
authors.affiliation: Department of Pediatric Allergy and Immunology, Kayseri Education and Research Hospital, Erkilet Kayseri, Turkey.
authors.forename: Hatice
authors.initials: H
authors.lastname: Eke Gungor
authors.affiliation: Department of Pediatric Allergy and Immunology, Kayseri Education and Research Hospital, Erkilet Kayseri, Turkey - umsahner@yahoo.com.
authors.forename: Umit M
authors.initials: UM
authors.lastname: Sahiner
authors.affiliation: Department of Pediatric Hematology, Kayseri Education and Research Hospital, Erkilet Kayseri, Turkey.
authors.forename: Yasemin
authors.initials: Y
authors.lastname: Altuner Torun
mesh_terms: D000293:Adolescent; D000420:Albuterol / Q000008:administration & dosage; D001249:Asthma / Q000175:diagnosis* / Q000503:physiopathology; D001993:Bronchodilator Agents / Q000008:administration & dosage*; D016022:Case-Control Studies; D002648:Child; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D008450:Maximal Midexpiratory Flow Rate; D065631:Rhinitis, Allergic / Q000175:diagnosis* / Q000503:physiopathology; D013147:Spirometry / Q000379:methods*; D014797:Vital Capacity
chemical_list: D001993:Bronchodilator Agents; D000420:Albuterol