title: Development of atopic dermatitis during the first 3 years of life: the Copenhagen prospective study on asthma in childhood cohort study in high-risk children.
abstract: OBJECTIVE
  To describe the development of atopic dermatitis (AD) during the first 3 years of life and identify the localization of the early skin lesions that predicts the development of AD.
  
  
  METHODS
  Prospective, longitudinal, birth cohort study of children born to mothers with a history of asthma, followed up for 3 years with scheduled visits every 6 months as well as visits for onset or acute exacerbations of skin symptoms.
  
  
  METHODS
  The cohort was recruited from greater Copenhagen, Denmark, and followed up at a clinical research unit, which controlled all diagnoses and treatment of skin diseases.
  
  
  METHODS
  A total of 411 infants were enrolled in the cohort; 55 had incomplete follow-up and were excluded from certain analyses.
  
  
  METHODS
  Atopic dermatitis was defined based on the criteria of Hanifin and Rajka, and severity was assessed by the SCORAD (Scoring Atopic Dermatitis) index. Predictive odds ratios of early skin lesions for those who developed AD vs those who did not were calculated.
  
  
  RESULTS
  The cumulative incidence of AD by age 3 years was 44% (155/356). The prevalence rate peaked at age 2 years for boys and at age 2.5 years for girls, but there were no other sex differences in the proportion of children developing AD. Skin involvement in infants with AD was found to begin at the scalp, forehead, ear, and neck in a balaclava-like pattern and continue to the extensor sides and trunk, finally affecting the flexor sides of the extremities. Early skin lesions of arms and joints best predicted AD at age 3 years.
  
  
  CONCLUSIONS
  Atopic dermatitis begins at the scalp, forehead, ear, and neck in a balaclava-like pattern. Eczema at the arms and joints provides the highest predictive value for the development of AD at age 3 years. This may be used for early prediction and intervention of AD.
authors.affiliation: Danish Pediatric Asthma Centre, Department of Pediatrics, Copenhagen University Hospital, Gentofte, Denmark.
authors.forename: Liselotte Brydensholt
authors.initials: LB
authors.lastname: Halkjaer
authors.forename: Lotte
authors.initials: L
authors.lastname: Loland
authors.forename: Frederik F
authors.initials: FF
authors.lastname: Buchvald
authors.forename: Tove
authors.initials: T
authors.lastname: Agner
authors.forename: Lone
authors.initials: L
authors.lastname: Skov
authors.forename: Matthew
authors.initials: M
authors.lastname: Strand
authors.forename: Hans
authors.initials: H
authors.lastname: Bisgaard
mesh_terms: D000367:Age Factors; D001249:Asthma / Q000150:complications; D002675:Child, Preschool; D015331:Cohort Studies; D003718:Denmark / Q000453:epidemiology; D003876:Dermatitis, Atopic / Q000150:complications / Q000453:epidemiology* / Q000503:physiopathology; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008137:Longitudinal Studies; D008297:Male; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D012737:Sex Factors