title: Early childhood risk factors for rhinoconjunctivitis in adolescence: a prospective birth cohort study.
abstract: BACKGROUND
  Rhinoconjunctivitis is a global health problem and one of the most common chronic conditions in children. Development of rhinoconjunctivitis depends on both genetic and environmental factors. Many studies have investigated rhinoconjunctivitis, but only few studies have evaluated the risk factors for non-allergic rhinoconjunctivitis in children finding family history of atopic diseases and gender to be of importance. The aim of this study was to investigate possible risk factors in early life for rhinoconjunctivitis, allergic as well as non-allergic, in adolescence.
  
  
  METHODS
  The children in the Danish Allergy Research Center cohort were examined eight times from birth to 14 years of age. Visits included questionnaire-based interview, clinical examination, skin prick test and specific IgE. We used univariate and multivariate logistic regression to investigate the relationship between early-life risk factors and the development of rhinoconjunctivitis, allergic as well as non-allergic, in adolescence.
  
  
  RESULTS
  Follow-up rate at 14-years was 66.2%. The prevalence of rhinoconjunctivitis was 32.8%. Family history of atopic diseases (aOR 2.25), atopic dermatitis (aOR 3.24), food allergy (aOR 3.89), early sensitization to inhalant and food allergens (aOR 2.92 and aOR 3.13) and male gender (aOR 1.90) were associated with allergic rhinoconjunctivitis but not with non-allergic rhinoconjunctivitis. Early environmental tobacco exposure was inversely associated with rhinoconjunctivitis (aOR 0.42), allergic (aOR 0.47) as well as non-allergic (aOR 0.43).
  
  
  CONCLUSIONS
  Different patterns of associations were revealed when stratifying rhinoconjunctivitis in allergic and non-allergic suggesting that allergic rhinoconjunctivitis and non-allergic-rhinoconjunctivitis are different phenotypes.
authors.affiliation: Department of Dermatology and Allergy Center, Odense Research Centre for Anaphylaxis (ORCA), Odense University Hospital, University of Southern Denmark, 5000 Odense C, Denmark.|Hans Christian Andersen Children's Hospital, Odense University Hospital, University of Southern Denmark, Sdr. Boulevard 29, 5000 Odense C, Denmark.
authors.forename: Elisabeth Soegaard
authors.identifier: 0000-0003-4711-2686
authors.initials: ES
authors.lastname: Christiansen
authors.affiliation: Department of Dermatology and Allergy Center, Odense Research Centre for Anaphylaxis (ORCA), Odense University Hospital, University of Southern Denmark, 5000 Odense C, Denmark.
authors.forename: Henrik Fomsgaard
authors.initials: HF
authors.lastname: Kjaer
authors.affiliation: Department of Dermatology and Allergy Center, Odense Research Centre for Anaphylaxis (ORCA), Odense University Hospital, University of Southern Denmark, 5000 Odense C, Denmark.
authors.forename: Esben
authors.initials: E
authors.lastname: Eller
authors.affiliation: Department of Dermatology and Allergy Center, Odense Research Centre for Anaphylaxis (ORCA), Odense University Hospital, University of Southern Denmark, 5000 Odense C, Denmark.
authors.forename: Carsten
authors.initials: C
authors.lastname: Bindslev-Jensen
authors.affiliation: Hans Christian Andersen Children's Hospital, Odense University Hospital, University of Southern Denmark, Sdr. Boulevard 29, 5000 Odense C, Denmark.
authors.forename: Arne
authors.initials: A
authors.lastname: Høst
authors.affiliation: Department of Dermatology and Allergy Center, Odense Research Centre for Anaphylaxis (ORCA), Odense University Hospital, University of Southern Denmark, 5000 Odense C, Denmark.
authors.forename: Charlotte Gotthard
authors.initials: CG
authors.lastname: Mortz
authors.affiliation: Hans Christian Andersen Children's Hospital, Odense University Hospital, University of Southern Denmark, Sdr. Boulevard 29, 5000 Odense C, Denmark.
authors.forename: Susanne
authors.initials: S
authors.lastname: Halken
keywords: Adolescence; Birth cohort; Logistic regression; Predictors; Rhinoconjunctivitis; Risk factor