title: Developmental profiles of eczema, wheeze, and rhinitis: two population-based birth cohort studies.
abstract: BACKGROUND
  The term "atopic march" has been used to imply a natural progression of a cascade of symptoms from eczema to asthma and rhinitis through childhood. We hypothesize that this expression does not adequately describe the natural history of eczema, wheeze, and rhinitis during childhood. We propose that this paradigm arose from cross-sectional analyses of longitudinal studies, and may reflect a population pattern that may not predominate at the individual level.
  
  
  RESULTS
  Data from 9,801 children in two population-based birth cohorts were used to determine individual profiles of eczema, wheeze, and rhinitis and whether the manifestations of these symptoms followed an atopic march pattern. Children were assessed at ages 1, 3, 5, 8, and 11 y. We used Bayesian machine learning methods to identify distinct latent classes based on individual profiles of eczema, wheeze, and rhinitis. This approach allowed us to identify groups of children with similar patterns of eczema, wheeze, and rhinitis over time. Using a latent disease profile model, the data were best described by eight latent classes: no disease (51.3%), atopic march (3.1%), persistent eczema and wheeze (2.7%), persistent eczema with later-onset rhinitis (4.7%), persistent wheeze with later-onset rhinitis (5.7%), transient wheeze (7.7%), eczema only (15.3%), and rhinitis only (9.6%). When latent variable modelling was carried out separately for the two cohorts, similar results were obtained. Highly concordant patterns of sensitisation were associated with different profiles of eczema, rhinitis, and wheeze. The main limitation of this study was the difference in wording of the questions used to ascertain the presence of eczema, wheeze, and rhinitis in the two cohorts.
  
  
  CONCLUSIONS
  The developmental profiles of eczema, wheeze, and rhinitis are heterogeneous; only a small proportion of children (∼ 7% of those with symptoms) follow trajectory profiles resembling the atopic march. Please see later in the article for the Editors' Summary.
authors.affiliation: Centre for Respiratory Medicine and Allergy, Institute of Inflammation and Repair, University of Manchester and University Hospital of South Manchester, Manchester, United Kingdom; Centre for Health Informatics, Institute of Population Health, University of Manchester, Manchester, United Kingdom.
authors.forename: Danielle C M
authors.initials: DC
authors.lastname: Belgrave
authors.affiliation: School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom.
authors.forename: Raquel
authors.initials: R
authors.lastname: Granell
authors.affiliation: Centre for Respiratory Medicine and Allergy, Institute of Inflammation and Repair, University of Manchester and University Hospital of South Manchester, Manchester, United Kingdom.
authors.forename: Angela
authors.initials: A
authors.lastname: Simpson
authors.affiliation: Microsoft Research Cambridge, Cambridge, United Kingdom.
authors.forename: John
authors.initials: J
authors.lastname: Guiver
authors.affiliation: Microsoft Research Cambridge, Cambridge, United Kingdom.
authors.forename: Christopher
authors.initials: C
authors.lastname: Bishop
authors.affiliation: Centre for Health Informatics, Institute of Population Health, University of Manchester, Manchester, United Kingdom.
authors.forename: Iain
authors.initials: I
authors.lastname: Buchan
authors.affiliation: School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom.
authors.forename: A John
authors.initials: AJ
authors.lastname: Henderson
authors.affiliation: Centre for Respiratory Medicine and Allergy, Institute of Inflammation and Repair, University of Manchester and University Hospital of South Manchester, Manchester, United Kingdom.
authors.forename: Adnan
authors.initials: A
authors.lastname: Custovic
mesh_terms: D001499:Bayes Theorem; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004485:Eczema / Q000175:diagnosis* / Q000473:pathology; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D012135:Respiratory Sounds / Q000175:diagnosis*; D012220:Rhinitis / Q000175:diagnosis* / Q000473:pathology