The Changing Epidemiology of Inflammatory Bowel Disease: What Goes Up May Come Down.

Recent epidemiologic studies have shown that although the incidence of inflammatory bowel disease (IBD) is rapidly increasing in newly industrialized countries, at the turn of the 21st century the incidence had stabilized in the Western world. In this issue of Inflammatory Bowel Diseases, Torabi and colleagues present their findings on the temporal trends and geographic variations in IBD incidence in Manitoba from 1990 to 2012 using the Manitoba Health population registry and the University of Manitoba IBD epidemiology database. Their results demonstrate an overall decrease in the incidence of IBD during the study period. They also found significant regional variations in disease incidence within Manitoba, with rates of new diagnosis of IBD remaining high in several regions. Lastly, the study found that a higher proportion of the indigenous population had a lower rate of IBD. These findings provide new insights on the changing epidemiology of IBD in the Western world. The overall declining incidence of IBD and identification of persistently low and high-risk populations in Manitoba, which traditionally has had some of the highest incidence rates of IBD, is intriguing and can provide new avenues of research for epidemiologists in the field.