title: Different effects of sensitization to mites and pollens on asthma symptoms and spirometric indices in children: a population-based cohort study.
abstract: BACKGROUND
  We have previously shown that long-term exposure of children to a highly polluted urban compared with a rural environment is associated with subclinical airway narrowing and increased prevalence of atopy.
  
  
  OBJECTIVE
  To test the hypothesis that sensitization to indoor perennial, compared with seasonal, aeroallergens has distinct effects on asthma symptoms and/or spirometric indices.
  
  
  METHODS
  We evaluated the respiratory health of 478 and 342 children aged 8 to 10 years living in an urban and a rural area, respectively, during a period of 8 years. Children were evaluated by parental questionnaire in 3 phases, 1995 to 1996 (phase 1), 1999 to 2000 (phase 2), and 2003 to 2004 (phase 3), and by spirometry and skin prick testing to 9 common local aeroallergens in phases 1 and 2.
  
  
  RESULTS
  Sensitization to pollens was associated with current wheezing in phase 1 of the study (odds ratio [OR], 3.36; 95% confidence interval [CI], 1.71 to 6.62; P < .001) but not with spirometric indices. Sensitization to mites was negatively associated with forced expiratory volume in 1 second (95% CI, -7.26 to -0.90; P = .01) and forced expiratory flow at 50% of forced vital capacity (95% CI, -10.80 to -1.33; P = .01) in study phase 1 but not in phase 2.
  
  
  CONCLUSIONS
  Our results indicate that sensitization to mites is associated with insidious involvement of large and small airways, whereas sensitization to pollens is associated with childhood wheezing at the age of 8 to 10 years. Subsequent loss of these associations implies that risk factors other than allergy influence airway disease at a later age.
authors: Respiratory Unit, Department of Pediatrics, University Hospital of Patras, Rio-Patras, Greece. manthra@otenet.gr
authors: Michael B
authors: MB
authors: Anthracopoulos
authors: Eva
authors: E
authors: Mantzouranis
authors: Athanasios G
authors: AG
authors: Paliatsos
authors: George
authors: G
authors: Tzavelas
authors: Evagelia
authors: E
authors: Lagona
authors: Polyxeni
authors: P
authors: Nicolaidou
authors: Kostas N
authors: KN
authors: Priftis
mesh_terms: D000402:Airway Obstruction / Q000175:diagnosis; D000485:Allergens / Q000009:adverse effects; D000818:Animals; D001249:Asthma / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology* / Q000503:physiopathology; D002648:Child; D015331:Cohort Studies; D005260:Female; D005540:Forced Expiratory Flow Rates; D005541:Forced Expiratory Volume; D006115:Greece / Q000453:epidemiology; D006801:Humans; D007114:Immunization; D008297:Male; D008925:Mites / Q000276:immunology*; D011058:Pollen / Q000009:adverse effects / Q000276:immunology*; D012135:Respiratory Sounds; D012424:Rural Population; D012882:Skin Tests; D013147:Spirometry; D011795:Surveys and Questionnaires; D014505:Urban Population
chemical_list: D000485:Allergens