title: Does farm environment protect against type 1 diabetes mellitus?
abstract: OBJECTIVE
  Hygiene hypothesis has been shown valid in respect of allergies and asthma but has not been, however, sufficiently studied in relation to type 1 diabetes mellitus. This study investigates the effect of childhood farm environment on the prevalence of type 1 diabetes mellitus in Finnish children and young adults.
  
  
  METHODS
  Data come from a questionnaire study carried out in 2007 (N = 5805). Prevalence of type 1 diabetes mellitus was analysed according to the type of the rural exposure below the age of 18 years. Associations were estimated and tested using Bayesian methods.
  
  
  RESULTS
  Consistent suggestive evidence of the inverse association of childhood's farm environment with the occurrence of type 1 diabetes mellitus was shown, even though conclusive results were not reached.
  
  
  CONCLUSIONS
  Exposure to a broad variety of non-pathogenic environmental microorganisms during childhood might have a protective effect on type 1 diabetes mellitus. Results clearly suggest that further research is well grounded with larger samples.
authors: Department of Public Health, Hjelt Institute, University of Helsinki, Helsinki, Finland. sanna.mm.heikkinen@helsinki.fi
authors: Sanna M M
authors: SM
authors: Heikkinen
authors: Janne M
authors: JM
authors: Pitkäniemi
authors: Maritta L
authors: ML
authors: Kilpeläinen
authors: Markku J
authors: MJ
authors: Koskenvuo
mesh_terms: D000328:Adult; D003922:Diabetes Mellitus, Type 1 / Q000453:epidemiology* / Q000517:prevention & control; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D012423:Rural Health; D012424:Rural Population / Q000706:statistics & numerical data; D011795:Surveys and Questionnaires
keywords: Type 1 diabetes; epidemiology; farm; hygiene hypothesis; living environment; microbial deprivation