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Review
. 2014 Feb 7;20(5):1238-47.
doi: 10.3748/wjg.v20.i5.1238.

Epidemiological studies of migration and environmental risk factors in the inflammatory bowel diseases

Yanna Ko  1 , Rhys Butcher  1 , Rupert W Leong  1
Affiliations
Review

Epidemiological studies of migration and environmental risk factors in the inflammatory bowel diseases

Yanna Ko et al. World J Gastroenterol. .

Abstract

Inflammatory bowel diseases (IBD) are idiopathic chronic diseases of the gastrointestinal tract well known to be associated with both genetic and environmental risk factors. Permissive genotypes may manifest into clinical phenotypes under certain environmental influences and these may be best studied from migratory studies. Exploring differences between first and second generation migrants may further highlight the contribution of environmental factors towards the development of IBD. There are few opportunities that have been offered so far. We aim to review the available migration studies on IBD, evaluate the known environmental factors associated with IBD, and explore modern migration patterns to identify new opportunities and candidate migrant groups in IBD migration research.

Keywords: Crohn’s disease; Environment; Epidemiology; Hygiene hypothesis; Inflammatory bowel disease; Risk factor; Ulcerative colitis.

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Figures

Figure 1
Figure 1
Included and excluded articles. IBD: Inflammatory bowel diseases.
Figure 2
Figure 2
Summary of standardized incidence ratio for Crohn’s disease and ulcerative colitis in second-generation immigrants (adapted from ref. [43]).
See this image and copyright information in PMC

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