title: Exposure to farming environments in early life and type 1 diabetes: a case-control study.
abstract: It has been hypothesized that a stimulation of regulatory cytokines by microbial compounds reduces autoimmune as well as atopic diseases. Farm-related contact to microbial compounds protects from allergies, but no data on the association between farm contact and type 1 diabetes is available. The aim of this study was to test this association. A case-control study was conducted in five children's hospitals. Regular contact to farm animals and potential confounders were assessed using a postal questionnaire. Eligible subjects were all prevalent cases with type 1 diabetes registered in the hospitals and hospital-based control subjects (response rate 91%). Included were children aged 6-16 years living in rural areas with German nationality (242 case and 224 control subjects). Regular contact to stables (adjusted odds ratio 1.2 [95% CI 0.5-2.7]) was not associated with type 1 diabetes. In addition, regular contact to specific farm animals was not associated with case status. There was a tendency for an inverse relationship between allergic rhinitis and type 1 diabetes (0.6 [0.3-1.1]; P = 0.11). There was no evidence that early exposure to farm animals largely decreases the risk in children for developing type 1 diabetes.
authors.affiliation: Unit for Occupational and Environmental Epidemiology and Net Teaching, Institute and Outpatient Clinic for Occupational and Environmental Medicine, Munich, Germany. katja.radon@med.uni-muenchen.de
authors.forename: Katja
authors.initials: K
authors.lastname: Radon
authors.forename: Doris
authors.initials: D
authors.lastname: Windstetter
authors.forename: Susanne
authors.initials: S
authors.lastname: Solfrank
authors.forename: Erika
authors.initials: E
authors.lastname: von Mutius
authors.forename: Dennis
authors.initials: D
authors.lastname: Nowak
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Schwarz
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000383:Agriculture; D000818:Animals; D000829:Animals, Domestic / Q000276:immunology*; D016022:Case-Control Studies; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000209:etiology* / Q000276:immunology*; D004781:Environmental Exposure; D005260:Female; D006801:Humans; D008297:Male; D016017:Odds Ratio; D012307:Risk Factors