A recent report reveals that Crohn’s disease and ulcerative colitis, collectively known as inflammatory bowel disease (IBD), effect almost twice as many US adults as previously thought. In the recent study,an estimated 3.1 million (1.3%) U.S. adults have been diagnosed with IBD. This is a significant increase from a report released in 1999 estimating that 1.8 million Americans (0.9%) were diagnosed with IBD.
IBD is an immune-mediated chronic inflammation of the gastrointestinal tract. Normally, the cells and proteins that make up the immune system protect you from infection. In people with IBD, however, the immune system mistakes food, bacteria, and other materials in the intestine for foreign or invading substances. When this happens, the body sends white blood cells into the lining of the intestines, where they produce chronic inflammation and ulcerations—called an autoimmune response.
Both Crohn’s disease and ulcerative colitis manifest as chronic immune-mediated inflammation of the gastrointestinal system. While they both cause similar symptoms, they are managed differently. Crohn’s disease may affect any part of the gastrointestinal system, from the mouth to the anus. Ulcerative colitis however, is limited to the colon, otherwise known as the large intestine.
Ulcerative colitis, unlike Crohn’s disease, can lead to colon cancer. People with ulcerative colitis get screened early and often for colon cancer. Screening guidelines recommend a colonoscopy performed a few years after diagnosis, and repeated every 1 to 2 years thereafter.
The recent study did not explore why the prevalence of IBD was higher than previously thought but did report that IBD was more common in adults 45 years or older. Non-Hispanic blacks had a lower prevelance of IBD compared to Hispanics and non-Hispanic whites. In addition, adults who were born in the US had a higher prevalence of IBD compared with adults born elsewhere. Poverty, level of education or residing in a suburban area were also related to a higher prevalence of IBD. The prevalence of IBD did not differ by sex, current marital status, health insurance coverage type, or region of residence.
This is an important study to understand the extensive burden of IBD to the US population.
Reference: Dahlhamer JM, Zammitti EP, Ward BW, Wheaton AG, Croft JB. Prevalence of Inflammatory Bowel Disease Among Adults Aged ≥18 Years — United States, 2015. MMWR Morb Mortal Wkly Rep 2016;65:1166–1169. DOI: http://dx.doi.org/10.15585/mmwr.mm6542a3.