Ulcerative colitis epidemiology

A resurgence of interest in dietary fiber has been stimulated by epidemiological evidence of differences in colonic disease patterns between cultures with diets containing large quantities of fiber, and Western cultures having more highly refined diets. Many African countries, for example, are relatively free of diverticular disease, ulcerative colitis, hemorrhoids, polyps, and cancer of the colon Whereas most interest has focused on the beneficial role of dietary fiber, there is also concern that high fiber diets may cause disturbances in the absorption of nutrients such as minerals (see Mineral Nutrients) and vitamins. 

The causal connection between NSAIDs and large bowel inflammation needs to be confirmed by appropriate epidemiological studies. Many publications have associated NSAID and colonic inflammation (SEDA-10, 77) (SEDA-15, 95), but the differential diagnosis between colonic inflammation arising de novo and exacerbation of underlying inflammatory bowel disease can be difficult, and the role of NSAIDs in aggravating ulcerative colitis or Crohn s disease or other inflammatory bowel disease is controversial (SEDA-10, 76) (SEDA-15, 95). A case-control study showed no association between appendi-cectomy for acute appendicitis and the use of NSAIDs (SEDA-22, 111). 

Monsen V, Sorstad J, Hellers G, et al. Extracolonic diagnosis in ulcerative colitis An epidemiologic study. Am J Gastroenterol 1990 85 711— 716. 

There is an epidemic of immune-mediated disease in highly-developed industrialized countries. Such diseases, like inflammatory bowel disease, multiple sclerosis and asthma increase in prevalence as populations adopt modem hygienic practices. These practices prevent exposure to parasitic worms (helminths). Epidemiologic studies surest that people who carry helminths have less immune-mediated disease. Mice colonized with helminths are protected from disease in models of cohtis, encephalitis. Type 1 diabetes and asthma. Clinical trials show that exposure to helminths reduce disease activity in patients with ulcerative colitis or Crohn s disease. This chapter reviews some of the work showing that colonization with helminths alters immune responses, against dysregulated inflammation. These helminth-host immune interactions have potentially important implications for the treatment of immune-mediated diseases. 

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