Epidemiology of inflammatory bowel disease in Spain. A systematic review

Background and objectives: Incidence and prevalence of Inflammatory Bowel D isease (IBD) differ considerably depending on the geographical region studi ed. In Spain. both Ulcerative Colitis (UC) and Crohn's Disease (CD) seem to have experienced an important change in terms of incidence during the past decades. Our aim was to systematically review the experience in Spain rega rding the epidemiology of IBD, in particular its incidence, its geographica l differences and its evolution over time. Methods: A bibliographical search till January 2000 was conducted in Intern et using the PubMed search motor and the following descriptors or key words : "Crohns disease", "Ulcerative colitis", "Inflammatory bowel disease", "Sp ain" and "Spanish". Only publications providing data on IBD incidence among Spanish patients were included. References from articles that fulfilled th e selection criteria were also reviewed. The endpoints considered in the re view were IBD incidence rate, its geographical differences, and its evoluti on over time. Results: UC incidence reported by different studies performed in Spain rang es from 0.6 to 8 cases/10(5)/year, with a mean value of 3.8. CD incidence r ates in Spain ranges from 0.4 to 5.5 cases/105/year, with a mean value of 1 .9. Some studies have shown differences in IBD incidence between regions in our country. Many studies have reported an increase in IBD incidence in Sp ain over time, although such increase is more evident in the case of CD. Conclusions: UC incidence in Spain ranges from 0.6 to 8 cases/105/year, wit h a mean value of 3.8. CD figures range from 0.4 to 5.5 cases/105/year. wit h an average rate of 1.9. IBD incidence seems to be relatively different de pending on the geographical region studied. Finally, several authors have d emonstrated an increase in IBD incidence in Spain over time, although such increase seems to be more evident in the case of CD. Consequently, IBD in S pain is no longer considered a rare disease, but a relatively frequent one.