Inflammatory bowel disease (IBD), once considered mainly a problem for industrialized Western countries, is now increasing in developing regions such as Africa, Asia, and Latin America. A new study published in Nature, conducted by an international consortium that includes researchers from the University of Chicago, provides a clearer understanding of how IBD spreads globally.
The research used data from more than 500 population-based studies across over 80 geographic regions to identify four distinct stages through which IBD progresses as it emerges and becomes established in a population. These findings are intended to help local health care systems prepare for and manage the growing number of patients with IBD.
The study was led by the Global IBD Visualization of Epidemiology Studies in the 21st Century (GIVES 21) consortium, headed by Gilaad G. Kaplan from the University of Calgary and Siew C. Ng from the Chinese University of Hong Kong. The GIVES21 group has created a large open-access repository of IBD epidemiology data available to researchers, clinicians, and patients worldwide.
“This has been a huge, collaborative effort to understand IBD around the globe,” said David T. Rubin, Joseph B. Kirsner Professor of Medicine at the University of Chicago.
“Now that we recognize what's happening with IBD in emerging areas of the world, we can start focusing on being able to treat it in places where these conditions are new,” said Rubin, who is also the newly elected chair of the International Organization for the study of IBD, which supported the new study.
“We can also study it in these emerging areas so we might get new clues as to what's driving this so we can help prevent it.”
Researchers analyzed data spanning a century on both annual diagnoses and total cases living with IBD. They found that regions move through predictable stages: initial emergence; rapid increase as societies industrialize; compounding prevalence; and finally an equilibrium stage where new cases balance out with deaths related to the disease. This final stage is expected to occur in some high-income regions by 2045.
Diet has been identified as one possible factor contributing to rising rates of IBD—specifically Western diets high in processed foods and animal products but low in fruits and vegetables. However, increases have also been observed in countries like India where vegetarianism is common, suggesting other factors are involved.
Rubin noted that food preparation methods and additives such as emulsifiers or microplastics may play a role. He emphasized that “IBD is really dozens of different conditions caused by many genetic and environmental factors.”
“By understanding where you're studying the disease, what you're looking at, and which people are developing IBD, you can get different ideas of what might be driving it, which will help us separate out these different types of IBD and find the right ways to treat them,” Rubin said.
Rubin directs UChicago’s Inflammatory Bowel Disease Center and plans to apply insights from global trends locally by launching an epidemiological study focused on Black and Latino populations on Chicago’s south and southwest sides—groups that often experience more severe forms of IBD due to disparities in diagnosis and access to care.
“Even though we have one of the largest IBD centers in the world, there's a clear disparity in diagnosis and access to expert care just a mile from here,” he said. “Taking something like this at a global level and getting down to the microcosm of the South Side of Chicago is incredibly important to find better ways to diagnose, treat and eventually prevent IBD our own patients.”
This article was originally published on the Biological Sciences Division website.