title: Environmental factors in familial Crohn's disease in Belgium.
abstract: BACKGROUND
  Environmental factors are believed to trigger the onset of Crohn's disease (CD) in genetically susceptible individuals. The aim of this study was to assess environmental and familial factors that might be etiologically related to CD.
  
  
  METHODS
  Twenty-one families with 3 or more affected first-degree relatives were studied, together with 10 matched control families. There were 74 patients with CD, 84 unaffected family members, and 59 controls. Family members were interviewed together at the parental home. A 176-item questionnaire delved into first symptoms, childhood vaccinations and diseases, food items, potable water supplies, social activities, travel, pets, and home and surrounding environment. Questions were directed specifically for 2 time-frames, childhood until age 20 and a 10-year epoch before the onset of first symptoms within a family. The possible factors linked to disease were evaluated using univariate and multivariate logistic regression.
  
  
  RESULTS
  There were significantly more smokers in the patients and their relatives than in controls. Patients had more appendicitis during adolescence, ate less oats, rye, and bran than controls, and consumed more unpasteurized cheese. Patients drank significantly less tap water and more well water than controls. Clustering of cases in time occurred in 13 of the 21 affected families.
  
  
  CONCLUSIONS
  The less frequent consumption of oats, rye, and bran and the more frequent eating of unpasteurized cheeses imitate potential dietary influences on gastrointestinal flora. More importantly, our data suggest that the drinking of well water represents an important risk factor for CD.
authors.affiliation: Department of Pathobiology, University of Connecticut, Storrs, Connecticut 06269-3089, USA. herbert.vankruiningen@uconn.edu
authors.forename: Herbert J
authors.initials: HJ
authors.lastname: Van Kruiningen
authors.forename: Marie
authors.initials: M
authors.lastname: Joossens
authors.forename: Severine
authors.initials: S
authors.lastname: Vermeire
authors.forename: Sofie
authors.initials: S
authors.lastname: Joossens
authors.forename: Stéphane
authors.initials: S
authors.lastname: Debeugny
authors.forename: Corinne
authors.initials: C
authors.lastname: Gower-Rousseau
authors.forename: Antoine
authors.initials: A
authors.lastname: Cortot
authors.forename: Jean-Frédéric
authors.initials: JF
authors.lastname: Colombel
authors.forename: Paul
authors.initials: P
authors.lastname: Rutgeerts
authors.forename: Robert
authors.initials: R
authors.lastname: Vlietinck
mesh_terms: D000293:Adolescent; D000328:Adult; D001530:Belgium; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D003424:Crohn Disease / Q000235:genetics*; D004032:Diet; D004522:Educational Status; D004777:Environment; D005260:Female; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D012111:Residence Characteristics; D012307:Risk Factors