Groundbreaking Study Led by the Crohn’s & Colitis Foundation Estimates Nearly 1 in 100 Americans Has Inflammatory Bowel Disease (IBD)

The most comprehensive study to date estimates prevalence, incidence, and racial and ethnic distribution of IBD, which includes Crohn’s disease and ulcerative colitis

Digestive System

July 20, 2023 – A groundbreaking study led by the Crohn’s & Colitis Foundation published today in Gastroenterology estimates the incidence, prevalence, and racial-ethnic distribution of physician-diagnosed IBD in the United States, using comprehensive health insurance claims data. The study, conducted by principal investigators at the Foundation, the University of Pennsylvania, University of North Carolina at Chapel Hill, and Carelon Research, finds that IBD is diagnosed in more than 0.7% of Americans, with 721 cases per 100,000 people, or nearly 1 in 100. This study is unique in having pulled data that are representative of nearly the entire U.S. population with health insurance.


Importantly, the study found significant differences in prevalence among different racial groups, with Whites having a rate of IBD that is 7 times higher than Blacks, 6 times higher than Hispanics, and 21 times higher than Asian Americans. More research is needed to understand the reasons for the racial-ethnic differences in IBD prevalence.


The study, named the Diversity within the INcidence, Prevalence, Treatment, and OUTcomes in Patients with IBD (INPUT) was funded by the Centers for Disease Control and Prevention (CDC).


To comprehensively estimate the full population of IBD patients in the U.S, the study’s investigators analyzed four different healthcare insurance claims datasets including national Medicare data, Medicaid data from five states, and two commercial health insurance companies. The researchers then calculated age, sex, and race-specific estimates of IBD incidence and prevalence and standardized these estimates to the 2018 United States Census.


IBD is an umbrella term used to describe disorders that cause chronic inflammation of the gastrointestinal (GI) tract. Symptoms include diarrhea, as well as abdominal pain, nausea, fever, loss of appetite, fatigue and at times rectal bleeding. The two most common forms of IBD are Crohn’s disease and ulcerative colitis. There are currently no cures for IBD.


“Accurate estimates of IBD incidence and prevalence taking into account racial and ethnic distribution are crucial because they provide valuable information about the burden of disease in a population, and patient’s healthcare needs,” said Andrés Hurtado-Lorenzo, PhD, Senior Vice President, Translational Research and IBD Ventures at the Crohn’s & Colitis Foundation, and Co-Principal Investigator of the INPUT study. “This is the most comprehensive study to date and this knowledge is essential to help healthcare professionals and policy makers allocate resources to effectively manage IBD, make better-informed public health decisions, and improve patient outcomes."


“This comprehensive evaluation of the racial and ethnic composition of IBD in the U.S. is an important step that not only allows clinicians to evaluate the degree to which current research adequately represents the full spectrum of IBD in the U.S. but also lays the foundation for establishing diversity benchmarks for future clinical studies,” said study Co-Principal Investigator Michael D. Kappelman, MD, MPH, Professor of Pediatrics and Adjunct Professor of Epidemiology at the University of North Carolina at Chapel Hill.


Co-Principal Investigator James D. Lewis, MD, MSCE, Professor of Medicine and Epidemiology at the Perelman School of Medicine at the University of Pennsylvania said, “It is difficult to obtain population-level health data in the U.S. due to the fragmented nature of our healthcare system. By leveraging different data sources that cover nearly the full spectrum of the U.S. population, these data clearly establish the U.S. as having one of the highest proportions of the population affected by IBD, and the numbers are continuing to rise.”

To access the article (10.1053/j.gastro.2023.07.003,) click here.

Contact: Rachel Peifer [email protected]


About the Crohn’s & Colitis Foundation

The Crohn's & Colitis Foundation is the leading nonprofit organization focused on both research and patient support for inflammatory bowel disease (IBD), with the mission of curing Crohn's disease and ulcerative colitis and improving quality of life for the millions of Americans living with IBD. The Foundation’s work is dramatically accelerating the research process, while also providing extensive educational and support resources for patients and their families, medical professionals, and the public. For more information, visit, call 888-694-8872, or email [email protected].