title: Preschool-age wheezing phenotypes and asthma persistence in adolescents.
abstract: BACKGROUND
  Predicting long-term outcomes in individuals with childhood wheezing is of major clinical relevance.
  
  
  OBJECTIVE
  To identify and characterize childhood wheezing phenotypes related to asthma persistence in adolescence with a multidimensional statistical model, independent of predefined hypotheses.
  
  
  METHODS
  This prospective cohort study included 308 children, ages < 7 years, with recurrent wheezing. We systematically evaluated asthma prevalence in children at 3, 8, and 13 years of follow-ups. Risk factors associated with asthma persistence in adolescence were analyzed with multivariable logistic regression. Early childhood wheezing phenotypes were identified with k-means cluster analysis of variables selected with the logistic regression analysis, which were based on questionnaires and skin-prick tests. These phenotypes were compared for predicting asthma prevalence, use of control treatments, and lung function in childhood and adolescence.
  
  
  RESULTS
  Asthma prevalence was 58.3% (n = 249) and 53.5% (n = 170) at the 8- and 13-year follow-ups, respectively. Preschool-age diagnoses of atopy (odds ratio 11.8 [95% confidence interval, 4.0-34.6]) and rhinitis (odds ratio 10.4 [95% confidence interval, 3.7-29.1]) were independent risk factors for asthma persistence in adolescence. We identified three early childhood wheezing phenotypes: transient, persistent atopic, and persistent nonatopic. The latter two were characterized by rhinitis during preschool age. These phenotypes could predict the following outcomes: asthma symptom persistence, use of control treatments, and lung function during childhood and adolescence (p < 0.03).
  
  
  CONCLUSIONS
  Asthma persistence through adolescence reflected different wheezing phenotypes based on preschool-age comorbidities, particularly rhinitis, with or without atopy. Our results supported that wheezing phenotypes, identified at early ages from simple measurements, could predict asthma and lung function outcomes.
authors.affiliation: Allergy Center, CUF Descobertas Hospital and CUF Infante Santo Hospital, Lisbon, Portugal.
authors.forename: Helena
authors.initials: H
authors.lastname: Pité
authors.forename: Ângela
authors.initials: Â
authors.lastname: Gaspar
authors.forename: Mário
authors.initials: M
authors.lastname: Morais-Almeida
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000175:diagnosis / Q000209:etiology*; D002675:Child, Preschool; D015331:Cohort Studies; D015897:Comorbidity; D005500:Follow-Up Studies; D006801:Humans; D018448:Models, Immunological; D010641:Phenotype; D011237:Predictive Value of Tests; D015995:Prevalence; D011446:Prospective Studies; D012135:Respiratory Sounds / Q000276:immunology*; D012307:Risk Factors