title: Predictors of allergen sensitization in Singapore children from birth to 3 years.
abstract: BACKGROUND
  Immune responses in allergic diseases begin with allergen sensitization, which usually occurs in childhood. Allergen sensitization involves a complex interplay of genetic and environmental factors, and sensitization patterns may change with age.
  
  
  OBJECTIVE
  To determine the predictors of allergen sensitization in the first 3 years of life in the growing up in Singapore towards healthy outcomes (GUSTO) prospective birth cohort study.
  
  
  METHODS
  Interviewers collected information on demographics, family history of allergy, social and lifestyle factors, and the child's health. We analyzed data from 849 children who completed skin prick testing (SPT) to inhalant allergens (house dust mites:Dermatophagoides pteronyssinus,Dermatophagoides farinae,andBlomia tropicalis) and food allergens (egg, peanut and cow's milk) to assess risk factors for allergen sensitization at 18 months. To ensure that clinical phenotypes preceded allergen sensitization, we also analyzed data from 649 children who had a negative skin prick test at 18 months and completed skin prick testing at 36 months.
  
  
  RESULTS
  We observed a significant association between eczema reported before 18 months and a positive SPT at 18 months [aOR 4.5 (1.9-10.7)]. Ninety-five (14.6 %) children with negative SPTs at 18 months developed positive tests at 36 months. Onset of eczema before 18 months was associated with an increased risk of new allergen sensitization at 36 months among children non-sensitized at 18 months [aOR 3.4 (1.2-9.3)]. An association was seen between wheeze reported before 18 months and new allergen sensitization at 36 months [aOR 3.2 (1.1-9.1)]. We found no significant association, however, between rhinitis reported before 18 months and new allergen sensitization at 36 months.
  
  
  CONCLUSIONS
  Early onset of eczema and wheeze are risk factors for later allergen sensitization, suggesting a possible increased susceptibility to allergen exposure through an impaired skin barrier or defective airway epithelium.Trial registrationNCT01174875 Registered 1 July 2010, retrospectively registered.
authors: Singapore Institute for Clinical Sciences (SICS), Agency for Science, Technology and Research (ASTAR), Singapore, Singapore.
authors: Evelyn Xiu Ling
authors: EX
authors: Loo
authors: National University of Singapore, Singapore, Singapore.
authors: Jordan Zheng Ting
authors: JZ
authors: Sim
authors: Allergy Service, Department of Paediatrics, KK Women's and Children's Hospital Singapore, Singapore, Singapore.
authors: Anne
authors: A
authors: Goh
authors: Respiratory Service Medicine, Department of Paediatrics, KK Women's and Children's Hospital, Singapore, Singapore.
authors: Oon Hoe
authors: OH
authors: Teoh
authors: Biostatistics Unit, Yong Loo Lin School of Medicine, National University Health System, Singapore, Singapore.
authors: Yiong Huak
authors: YH
authors: Chan
authors: Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore.
authors: Seang Mei
authors: SM
authors: Saw
authors: Department of Maternal Fetal Medicine, KK Women's and Children's Hospital (KKH), Singapore, Singapore.
authors: Kenneth
authors: K
authors: Kwek
authors: Growth, Development and Metabolism Programme, Singapore Institute for Clinical Sciences (SICS), Agency for Science, Technology and Research (ASTAR), Singapore, Singapore ; Liggins Institute, University of Auckland, Auckland, New Zealand.
authors: Peter D
authors: PD
authors: Gluckman
authors: NIHR Southampton Biomedical Research Centre, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, SO16 6YD UK ; Medical Research Council Lifecourse Epidemiology Unit, Southampton, SO16 6YD UK.
authors: Keith M
authors: KM
authors: Godfrey
authors: Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, Level 12, NUHS Tower Block, Singapore, 119228 Singapore ; Khoo Teck Puat-National University Children's Medical Institute, National University Hospital, National University Health System, Singapore, Singapore.
authors: Hugo
authors: H
authors: Van Bever
authors: Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
authors: Yap Seng
authors: YS
authors: Chong
authors: Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, Level 12, NUHS Tower Block, Singapore, 119228 Singapore.
authors: Bee Wah
authors: BW
authors: Lee
authors: Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore ; Department of Epidemiology, Biostatistics and Occupational Health, McGill University Faculty of Medicine, Montreal, Canada ; Department of Pediatrics, McGill University Faculty of Medicine, Montreal, Canada.
authors: Michael S
authors: MS
authors: Kramer
authors: Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, Level 12, NUHS Tower Block, Singapore, 119228 Singapore ; Khoo Teck Puat-National University Children's Medical Institute, National University Hospital, National University Health System, Singapore, Singapore.
authors: Lynette Pei-Chi
authors: LP
authors: Shek
keywords: Allergen sensitization; Eczema; Predictors; Skin barrier; Wheeze