Update on the incidence and prevalence of Crohnʼs disease and ulcerative colitis in Olmsted County, Minnesota, 1940–2000

Although incidence rates of CD and UC increased after 1940, they have remained stable over the past 30 years. Since 1991 the prevalence of UC decreased by 7%, and the prevalence of CD increased about 31%. Extrapolating these figures to US Census data, there were approximately 1.1 million people with inflammatory bowel disease in the US in 2000.