Background: Geographical differences, population migration, and changing demographics suggest an environmental role in prevalence, modulation, and phenotypic expression of inflammatory bowel disease (IBD).
Aim: To determine the incidence of IBD and disease subtype in the pediatric South Asian population in British Columbia (BC) compared with non-South Asian IBD patients in the same geographic area.
Methods: Chart review with data collected for all patients <or=16 yr of age diagnosed with IBD at B.C. Children's hospital, January 1985 to June 2005. Age, gender, family history, duration of symptoms, type, and extent of disease were extracted. Identified South Asian subjects were prospectively interviewed.
Results: Seventy-five South Asian patients were diagnosed with IBD, 48% Crohn's disease (CD), 33.3% ulcerative colitis (UC), and 18.7% with indeterminate colitis (IC), in contrast to 71%, 18.8%, and 10.2%, respectively, in the non-South Asian population. The incidence rate for South Asian IBD patients, for the period 1996-2001 was 15.19/10(5) (6.41/10(5) for CD, 6.70/10(5) for UC, and 2.08/10(5) for IC) compared with 5.19/10(5) for the non-South Asian IBD group (3.69/10(5), 0.96/10(5), and 0.54/10(5), respectively). The South Asian male/female ratio was significantly different from that observed for the rest of the population.
Conclusion: These data suggest a significantly higher incidence of IBD in the South Asian pediatric population compared with the rest of the BC pediatric population, with a different pattern of phenotypic expression, a male predominance, and more extensive colonic disease. These data suggest a potential effect of migration, and environmental and lifestyle change on the incidence of IBD and disease subtype.