Natural history of inflammatory bowel disease: a comparison between the East and the West.

Over the past decades, there has been a rapid increase in the incidence and prevalence of inflammatory bowel disease (IBD) in Asia. The natural history of IBD in Asian patients could be different from that in Western patients due to variations in disease phenotypes and genotypes as well as the healthcare environment between the 2 populations. To adequately cope with this disease, it is important to fully understand the potential differences in its natural history among different populations. In this review, we evaluated the differences in the clinical course of IBD between Asian and Western patients with regards to phenotypic progression, hospitalization, major surgery, risk of colorectal cancer, and mortality, mainly based on the results of population-based studies. The findings of our narrative review suggest that the clinical course of Asian patients with IBD, especially ulcerative colitis, is better than that of Western patients, as indicated by the lower rates of major surgery and hospitalization. In addition, similar to Western patients, the clinical course of Asian patients with IBD has been improving as evidenced by the decreasing rates of disease behavior progression (in Crohn's disease), hospitalization, and major surgery.