title: Aeroallergen sensitization correlates with PC(20) and exhaled nitric oxide in subjects with mild-to-moderate asthma.
abstract: BACKGROUND
  Aeroallergen sensitization in adult asthmatic patients from a wide geographic area has not been correlated with patients' characteristics, markers of airways inflammation, and lung function.
  
  
  OBJECTIVE
  We assessed data obtained from the Asthma Clinical Research Network trials to determine the relationship of aeroallergen sensitization to age, sex, ethnicity, and markers of inflammation and airways function.
  
  
  METHODS
  Skin testing (14 epicutaneous) was performed on 1338 subjects with objectively diagnosed mild-to-moderate asthma from 11 Asthma Clinical Research Network studies. Skin testing used identical techniques and a quality assurance program to ensure uniformity across centers.
  
  
  RESULTS
  Ninety-five percent of the subjects had at least 1 positive skin test response. Of these, 14% had positive reactions to 1 or 2 allergens and 81% had positive reactions to 3 or more allergens, and 2% of subjects reacted only to seasonal allergens, 26% only to perennial allergens, and 67% to both. Increasing IgE and exhaled nitric oxide values, decreasing PC(20) values, and minority ethnicity significantly correlated with the number of positive skin test responses. Subjects with late-onset asthma were less likely to be sensitized; nonetheless, 89% of subjects older than 60 years had positive responses.
  
  
  CONCLUSIONS
  Ninety-five percent of patients with mild-to-moderate asthma might have an allergic component. Age does not significantly affect aeroallergen sensitization, but the pattern of allergic sensitization varies with ethnicity and geography. Measures used to characterize asthma, such as IgE, exhaled nitric oxide, and PC(20) values, are correlated with aeroallergen sensitization.
authors.affiliation: Division of Pulmonary Care, Pennsylvania State University College of Medicine, Hershey, PA 17033-0853, USA. tcraig@psu.edu
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Craig
authors.forename: Tonya S
authors.initials: TS
authors.lastname: King
authors.forename: Robert F
authors.initials: RF
authors.lastname: Lemanske
authors.forename: Michael E
authors.initials: ME
authors.lastname: Wechsler
authors.forename: Nikolina
authors.initials: N
authors.lastname: Icitovic
authors.forename: Ronald R
authors.initials: RR
authors.lastname: Zimmerman
authors.forename: Stephen
authors.initials: S
authors.lastname: Wasserman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000393:Air Pollutants / Q000276:immunology; D000485:Allergens / Q000276:immunology; D001249:Asthma / Q000150:complications* / Q000453:epidemiology / Q000276:immunology; D002648:Child; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000150:complications* / Q000453:epidemiology* / Q000276:immunology; D007073:Immunoglobulin E / Q000097:blood; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000032:analysis*; D015995:Prevalence; D012129:Respiratory Function Tests; D012882:Skin Tests
chemical_list: D000393:Air Pollutants; D000485:Allergens; D009569:Nitric Oxide; D007073:Immunoglobulin E