title: Inflammatory bowel disease epidemiology.
abstract: OBJECTIVE
  The occurrence of inflammatory bowel disease (IBD) is increasing worldwide, yet the reasons remain unknown. New therapeutic approaches have been introduced in medical IBD therapy, but their impact on the natural history of IBD remains uncertain. This review will summarize the recent findings in the epidemiology of IBD.
  
  
  RESULTS
  The incidence of IBD in western Europe is twice as high as in eastern Europe, whereas the highest IBD incidence in the world is found in the Faroe Islands. Early intervention with immunosuppressant and biological agents seems to have reduced the colectomy rates for ulcerative colitis, whereas the impact on Crohn's disease has yet to be determined. Mortality in Crohn's disease has not changed despite improvements in medical and surgical management. Specialized care in IBD centres, treatments to target and obtaining mucosal healing, early intervention at relapse and avoiding Clostridium difficile super infection might reduce the mortality rate in the future. The risk of colorectal cancer in Crohn's disease seems to be equivalent to the risk in ulcerative colitis. Patients with small bowel Crohn's disease are at increased risk of small bowel adenocarcinoma.
  
  
  CONCLUSIONS
  The natural disease course of IBD seems to change along with the new 'treat to target' goal of achieving intestinal mucosal healing. Future population-based studies of unselected IBD cohorts should be considered the gold standard for studies investigating these issues.
authors.affiliation: Medical Section, Digestive Disease Centre, Herlev University Hospital, Herlev, Copenhagen, Denmark.
authors.forename: Johan
authors.initials: J
authors.lastname: Burisch
authors.forename: Pia
authors.initials: P
authors.lastname: Munkholm
mesh_terms: D003082:Colectomy / Q000706:statistics & numerical data; D015179:Colorectal Neoplasms / Q000209:etiology; D006801:Humans; D015994:Incidence; D015212:Inflammatory Bowel Diseases / Q000150:complications / Q000453:epidemiology* / Q000601:surgery; D015995:Prevalence; D012307:Risk Factors