title: Increased risk of peanut allergy in infants of Asian-born parents compared to those of Australian-born parents.
abstract: BACKGROUND
  Asian infants appear to be over-represented among patients with clinical food allergy in Australia, but this has not been formally examined at the population level. Any difference in prevalence according to parental country of birth may be secondary to modifiable lifestyle factors. We aimed to quantify (i) differences in the prevalence of peanut allergy by parental country of birth and (ii) contribution of measured environmental exposures to these differences.
  
  
  METHODS
  The population-based HealthNuts study in Melbourne, Australia, screened 5276 infants (74% participation) with skin prick tests and sensitized infants underwent food challenge. Of these, 535 had a parent born in East Asia and 574 in UK/Europe. Associations between parents' country of birth and offspring peanut allergy were examined using multiple logistic regression.
  
  
  RESULTS
  Compared to infants with two Australian-born parents, peanut allergy was more common among infants with parent/s born in East Asia (OR 3.4, 95% CI 2.2-5.1) but not those with parent/s born in the UK/Europe (OR 0.8, 95% CI 0.4-1.5). Paradoxically rates of allergic disease were lower among Asian parents. A higher prevalence of eczema among infants of Asian parents explained around 30% of the increase in peanut allergy, while differences in dog ownership explained around 18%.
  
  
  CONCLUSIONS
  The high peanut allergy prevalence among infants of Asian-born parents appears to have occurred in a single generation and was not present among infants with parents migrating from other countries, suggesting gene-environment interactions are important. The role of eczema and microbial exposure in food allergy prevention warrants exploration.
authors.affiliation: Murdoch Childrens Research Institute, Royal Children's Hospital, University of Melbourne, Parkville, Vic., Australia; Centre for Epidemiology and Biostatistics, School of Population and Global Health, The University of Melbourne, Parkville, Vic., Australia.
authors.forename: J J
authors.initials: JJ
authors.lastname: Koplin
authors.forename: R L
authors.initials: RL
authors.lastname: Peters
authors.forename: A-L
authors.initials: AL
authors.lastname: Ponsonby
authors.forename: L C
authors.initials: LC
authors.lastname: Gurrin
authors.forename: D
authors.initials: D
authors.lastname: Hill
authors.forename: M L K
authors.initials: ML
authors.lastname: Tang
authors.forename: S C
authors.initials: SC
authors.lastname: Dharmage
authors.forename: K J
authors.initials: KJ
authors.lastname: Allen
mesh_terms: D000818:Animals; D001208:Asia; D044466:Asian People; D001315:Australia / Q000453:epidemiology / Q000208:ethnology; D005260:Female; D005512:Food Hypersensitivity / Q000453:epidemiology / Q000276:immunology; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology; D007223:Infant; D008297:Male; D018811:Maternal Exposure; D021183:Peanut Hypersensitivity / Q000453:epidemiology* / Q000276:immunology; D011159:Population Surveillance; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D015995:Prevalence; D012111:Residence Characteristics; D012306:Risk
chemical_list: D007073:Immunoglobulin E
keywords: food allergy; infant diet; migration; peanut allergy; peanut sensitization