Impact of obesity on the management of inflammatory bowel disease

The worldwide prevalence of obesity has reached staggering proportions, and the inflammatory bowel disease (IBD) population has not been immune to this trend, with obesity rates estimated to be between 15% and 40%. With the concurrent rise in incidence of IBD itself, there are biologically plausible mechanisms that suggest a potential role of obesity in the pathogenesis of IBD, although epidemiologic data on this issue are conflicting. Similarly, studies exploring the impact that obesity may have on the natural history of disease have produced inconsistent results. Some studies suggest higher and others lower rates of surgery in obese Crohn's disease patients, other studies suggest a higher risk of surgery in obese ulcerative colitis patients, and yet other studies reveal no difference in outcomes regarding hospitalization or surgery for either group. Regardless of its impact on the pathogenesis or natural history of IBD, the rising prevalence of obesity in this population results in a need to better understand the effect it has on IBD management. Although pharmacologic data suggest that obesity may influence the absorption, distribution, and clearance of the available therapeutic agents, the actual clinical consequences that these differences have on disease management are less clear. Finally, it is possible that weight loss interventions for obesity could have an impact on the clinical course of IBD.