AUSTIN, TEX. – With the increase in the prevalence of inflammatory bowel disease worldwide approaching pandemic proportions, personalized medicine targeting diet and the microbiome may contribute to a halt or even a reversal of the trend, a leading researcher from Israel and proponent of the Mediterranean diet reported at the Crohn’s & Colitis Congress®, a partnership of the Crohn's & Colitis Foundation and the American Gastroenterological Association.
Dr. Iris Dotan
“Inflammatory bowel disease is turning into a pandemic around the world,” said Iris Dotan, MD, of the Rabin Medical Center in Petah Tikva, Israel, citing research reported at the 2015 meeting of the European Crohn’s & Colitis Organization that showed the prevalence of inflammatory bowel disease (IBD) in Israel increasing almost 400% from 1991 to 2015, up to 460 per 100,000. “The rising incidence highlights the role of environmental factors,” she added.
She reported on her work with the Rabin Medical Center Pouch Cohort, which is studying the ileal pouch as a man-made model of IBD to get answers. “We believe that when patients progress from having a pouch that is normal to having pouchitis it actually resembles Crohn’s disease and can be used as a model to identify processes that are ongoing in these patients,” she said.
The study is following an unspecified number of ileal pouch patients prospectively, evaluating their biomaterial with stool samples and mucosal biopsies, and tracking their diet and psychosocial status to gain insight into what sets off episodes of pouchitis.
Already, the study has provided insight into how antibiotics may contribute to IBD. “Pouch disease is a very antibiotic-responsive disease,” she said in an interview. “Antibiotics are clinically effective. However, as we dive deeper into this and understand the mechanistics of it, we see that antibiotics cause more dysbiosis, which is something that is unwanted in patients with a pouch.”
A similar response has been shown in Crohn’s disease, she said. With antibiotics, “you’re doing something that might be helpful clinically for the short term; however, it might be harmful in the long term.”
When these patients stop antibiotic therapy, their dysbiosis increases and resistance wanes, she said. “These patients are replenished by other bacteria, probably some from the oral cavity, causing this circle so they would need recurrent courses of antibiotics.”
Evidence is accumulating that the Mediterranean diet can break that cycle, Dr. Dotan said, citing unpublished findings from her group that showed pouchitis patients consumed less fruit than counterparts without the disease. Dr. Dotan also cited a study published this year that found the Mediterranean diet is associated with a lower risk of Crohn’s disease later in life (Gut. 2020 Jan 3. doi: 10.1136/gutjnl-2019-319505).
Dr. Dotan’s research has shown that patients don’t have to adhere completely to the Mediterranean diet but can make less-drastic but significant changes. “You don’t need the whole program,” she said. “If you tell patients to start with something – increase fruits and vegetables – that’s not too complex. Then try to change some of the protein with legumes or other protein sources; that also would be helpful.” Another strategy is to direct patients away from processed foods with additives and preservatives.
“Microbial modifications, including antibiotics, probiotics, diet, and fecal microbial transplantation may have variable effects on specific patient populations, so we can’t be too long simplistic about these options,” she said.
Personalization of diet and microbial manipulations may do more than provide short-term treatment for patients, she said. “It might contribute to halting or even reversing the global increase we’ve seen in IBD recurrence over the past few years.”
Dr. Dotan disclosed financial relationships with AbbVie, Takeda, Pfizer, Genentech/Roche, Neopharm, and Gilead.
SOURCE: Dotan I. Crohn’s & Colitis Congress 2020, Presentation Sp75.