However, people with IBD do have a greater risk of death than the general population (people that do not have IBD). This is perhaps not surprising, but it can be a bit confusing. There are a great many reasons someone with IBD might die: complications from surgery, a reaction to medication, developing a serious related condition (such as a liver disease or toxic megacolon). In some cases, it's unknown if a person's IBD actually contributed to their death or not.
One study of 692 patients in Minnesota found that the overall life expectancy of people with IBD was "similar" to those who do not have IBD. For those with Crohn's disease, cause of death from gastrointestinal disorders and chronic obstructive pulmonary disease (COPD) were more common than in the general public. The authors indicate that stopping smoking is crucial for patients with Crohn's disease. For those with ulcerative colitis, there was actually a decrease in the deaths from cardiovascular disease. The authors explain that this could be from a low incidence of smoking in ulcerative colitis patients, and low levels of sodium and water in the body due to ileostomy or extensive colitis.
A second study in England showed that the most deaths occurred in the first year after diagnosis, but most of those deaths were not from IBD, but from some other cause. A very severe first flare-up or Crohn's disease in the colon or the perianal area were also correlated with increased mortality. The authors also point out that older patients who are recently diagnosed with IBD may be at increased risk of dying.
Overall, IBD is not generally a fatal condition, but as with any condition, it is important to seek treatment and develop an overall healthy lifestyle.
James D. Lewis, Joel M. Gelfand, Andrea B. Troxel, Kimberly A. Forde, Craig Newcomb, Hopiy Kim, David J. Margolis, and Brian L. Strom. "Immunosuppressant Medications and Mortality in Inflammatory Bowel Disease." Am J Gastroenterol 2008. 103:1–8. Jun 26 2008.
Jess T, Loftus EV Jr, Harmsen WS, Zinsmeister AR, Tremaine WJ, Melton LJ 3rd, Munkholm P, Sandborn WJ. "Survival and cause specific mortality in patients with inflammatory bowel disease: a long term outcome study in Olmsted County, Minnesota, 1940-2004." Gut 2006. Sep 55:1248-1254. Jun 26 2008.
Farrokhyar F, Swarbrick ET, Grace RH, Hellier MD, Gent AE, Irvine EJ. "Low mortality in ulcerative colitis and Crohn's disease in three regional centers in England." Am J Gastroenterol 2001 Feb 96:501-507. Jun 26 2008.