Asian ethnic origin and the risk of inflammatory bowel disease.

OBJECTIVE

To assess whether inflammatory bowel disease (IBD) is more prevalent in young Asians than Europeans living in Great Britain.

DESIGN

Longitudinal birth cohort study of all those born 5-11 April 1970 in Great Britain--the 1970 British Cohort Study (BCS70).

METHODS

The relationship of a diagnosis of ulcerative colitis or Crohn's disease by age 26 years with ethnic origin was investigated among 8,432 cohort members with complete data using multiple logistic regression. We adjusted for potential confounding factors, household crowding and sex, as well as for a family history of IBD.

RESULTS

Young Asians born in Britain were significantly more likely than indigenous Europeans to have a diagnosis of IBD by age 26 years, with relative odds of 6.10 (95% CI 2.14-17.33). This group of cohort members had ethnic origins in India, Pakistan or Bangladesh (although none of those from Bangladesh had IBD). This relationship remained statistically significant after adjustment for the potential confounding factors and family history of IBD.

CONCLUSION

Young Asians who were born in Britain are at a significantly higher risk of developing IBD than the indigenous European population. This may reflect a greater genetic predisposition to IBD that is uncovered by exposure to environmental factors.