Next steps: Pin down driving factors
“There is significant interest in the apparent increase in the incidence and prevalence of IBD, particularly in previously low incidence areas,” Edward L. Barnes, MD, MPH, of the University of North Carolina at Chapel Hill said in an interview.
“Many research groups and clinicians suspect that environmental exposures, including dietary exposures, may play a critical role in these trends,” said Dr. Barnes. “This study utilized a large, multinational prospective cohort design to assess the influence of diet on the risk of developing IBD,” which is particularly important considering the potential for processed foods and food additives to impact the gastrointestinal tract.
“The strong associations demonstrated by the authors were impressive, particularly given that the authors performed multiple subanalyses, including evaluations by participant age and evaluations of particular food groups/types [e.g., processed meat, soft drinks, and refined sweet foods],” he noted. Dr. Barnes also found the lack of association with intake of white meat and unprocessed red meat interesting. “In my opinion, these subanalyses strengthen the overall associations demonstrated by the authors given their prospective study design and their attention to evaluating all potential associations that may be driving the relationships present in this cohort.
“At this point, the take-home message for clinicians treating patients with Crohn’s disease and ulcerative colitis should be that this association exists,” said Dr. Barnes. “One question that remains is whether the same risk factors that are present for developing disease also influence the disease course, given that the primary outcome of this study was the development of IBD. Given that much of our data with regard to the interplay between diet and IBD are still emerging, physicians treating patients with IBD can make patients aware of these associations and the potential benefit of limiting ultraprocessed foods in their diet.”
For these important results to become actionable, “further research is likely necessary to identify the factors that are driving this association,” Dr. Barnes explained. “This would likely build on prior animal models that have demonstrated an association between food additives such as emulsifiers and changes in the gastrointestinal tract that could ultimately lead to increased inflammation and the development of IBD.” Such information about specific drivers “would then allow clinicians to determine which population would benefit most from dietary changes/recommendations.”
The overall PURE study was supported by the Population Health Research Institute, Hamilton Health Sciences Research Institute, Canadian Institutes of Health Research, Heart and Stroke Foundation of Ontario, CIHR’s Strategy for Patient Oriented Research through the Ontario SPOR Support Unit, and the Ontario Ministry of Health and Long-term Care. PURE also was supported in part by unrestricted grants from several pharmaceutical companies, notably AstraZeneca, Sanofi-Aventis, Boehringer Ingelheim, Servier, and GlaxoSmithKline. The researchers had no relevant financial conflicts to disclose. Dr. Barnes disclosed serving as a consultant for AbbVie, Gilead, Pfizer, Takeda, and Target RWE.