The incidence and prevalence of inflammatory bowel disease in North Tees Health District.

The experience with inflammatory bowel disease in a stable, defined population in northeast England is described. In this population, the incidence of inflammatory bowel disease was higher than expected. In particular, a high incidence of colorectal and anal Crohn's disease was found. The literature is reviewed in order to identify some of the factors responsible for this unusual prevalence of inflammatory bowel disease in the study population. No explanation for our unexpected findings can be advanced.