Incidence, Disease Phenotype at Diagnosis, and Early Disease Course in Inflammatory Bowel Diseases in Western Hungary, 2002-2006

Background: Recent trends indicate a change in the epidemiology of inflammatory bowel diseases (IBD), with previously low incidence areas now reporting a progressive rise in the incidence. Our aim was to analyze the incidence and disease phenotype at diagnosis in IBD in the population-based Veszprem Province database, which included incident patients diagnosed between January 1, 2002 and December 31, 2006. Methods: Data of 393 incident patients were analyzed (ulcerative colitis [UC]: 220, age-at-diagnosis: 40.5 years; Crohn's disease [CD]: 163, age-at-diagnosis: 32.5 years; and indeterminate colitis [IC]: 10). Both hospital and outpatient records were collected and comprehensively reviewed. Results: Adjusted mean incidence rates were 8.9/10(5) person-years for CD and 11.9/10(5) person-years in UC. Peak onset age in both CD and UC patients was 21-30 years old. Location at diagnosis in UC was proctitis in 26.8%, left-sided colitis in 50.9%, and pancolitis in 22.3%. The probability of proximal extension and colectomy after 5 years was 12.7% and 2.8%. The disease location in CD was ileal in 20.2%, colonic in 35.6%, ileocolonic in 44.2%, and upper gastrointestinal in four patients. Behavior at diagnosis was stenosing/penetrating in 35.6% and perianal in 11.1%. Patients with colonic disease were older at diagnosis compared to patients with ileal or ileocolonic disease. In a Kaplan-Meier analysis, probability of surgical resection was 9.8%, 18.5%, and 21.3% after 1, 3, and 5 years of disease duration, respectively. Conclusions: The incidence of IBD in Veszprem Province in the last decade was high, equal to that in high-incidence areas in Western European countries. Early disease course is milder compared to data reported in the literature.