title: Environmental factors associated with Crohn's disease in India.
abstract: BACKGROUND
  The frequency of diagnosis of Crohn's disease (CD) in India is increasing. This case-control study was designed to detect associations of environmental and dietary factors with the diagnosis of CD.
  
  
  METHODS
  In 200 consecutive patients with CD and 200 control subjects without gastrointestinal disease, environmental hygiene exposures in childhood and in the past one year, and dietary preferences were recorded using a questionnaire. Univariate and multivariate analyses were done.
  
  
  RESULTS
  In univariate analysis, CD showed positive association with urban residence (at birth and current), availability of protected drinking water (childhood and current), availability of piped water in the house (childhood and current), and strict vegetarian dietary habit, and negative association with regular fish consumption and presence of cattle in the house compound. Multivariate analysis showed that regular fish consumption (OR 0.52, 95% CI 0.33-0.80, p = 0.003), and presence of cattle in the house compound currently (OR 0.57, 95% CI 0.35-0.92, p = 0.023) were significant protective associations, whereas use of safe drinking water was positively associated (OR 1.59, 95% CI 1.02-2.47, p = 0.042) with the disease.
  
  
  CONCLUSIONS
  Occurrence of CD was associated with dietary and environmental exposures, which indicate that diet and hygiene may influence the development of this disease.
authors.affiliation: Department of Gastrointestinal Sciences, Christian Medical College, Vellore, India.
authors.forename: Srinivasan
authors.initials: S
authors.lastname: Pugazhendhi
authors.forename: Manoj Kumar
authors.initials: MK
authors.lastname: Sahu
authors.forename: Venkataraman
authors.initials: V
authors.lastname: Subramanian
authors.forename: Anna
authors.initials: A
authors.lastname: Pulimood
authors.forename: Balakrishnan S
authors.initials: BS
authors.lastname: Ramakrishna
mesh_terms: D000328:Adult; D000818:Animals; D000829:Animals, Domestic; D016022:Case-Control Studies; D002417:Cattle; D003247:Conservation of Natural Resources / Q000379:methods* / Q000706:statistics & numerical data; D003424:Crohn Disease / Q000453:epidemiology / Q000209:etiology; D014676:Diet, Vegetarian; D060766:Drinking Water / Q000009:adverse effects; D004781:Environmental Exposure / Q000517:prevention & control / Q000706:statistics & numerical data; D005260:Female; D005396:Fish Products; D005523:Food Supply; D006801:Humans; D006920:Hygiene / Q000592:standards*; D007194:India / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012499:Sanitation / Q000379:methods / Q000592:standards; D012907:Smoking / Q000009:adverse effects; D011795:Surveys and Questionnaires
chemical_list: D060766:Drinking Water