Exploring the Relationship Between Bariatric Surgery and Inflammatory Bowel Disease: A Systematic Review

Background Obesity affects over 40% of Americans. Bariatric surgery is an increasingly popular and well-studied method to achieve weight loss, improve metabolic homeostasis, and resolve obesity-related comorbid conditions. While the impact of bariatric surgery on weight loss and metabolic health has been extensively studied, there is an increasing body of literature characterizing the impact of bariatric surgery on gastrointestinal health and inflammation. Inflammatory bowel disease (IBD) leads to inflammation in both the small and large intestine, and leads to significant patient morbidity. Similar to obesity, the incidence of IBD is also rising. Patients with IBD and obesity may seek bariatric surgery. The impact of bariatric surgery on IBD is not well understood, but critical to understand for optimal patient care. Herein, we review the currently available literature on the impact of bariatric surgery on IBD including common trends, discrepancies in findings, and remaining knowledge gaps in need of further study. Methods A systematic review of the PubMed/MEDLINE database using PRISMA guidelines was performed. Results We identified 12 manuscripts discussing de novo IBD after bariatric surgery and 16 studying bariatric surgery in patients with pre-existing IBD. Overall, bariatric surgery appears to be safe in patients with pre-existing IBD but may increase the risk of developing de novo IBD. Conclusions Further research into optimal surgical approaches, patient selection, and mechanisms on how bariatric surgery impacts IBD is needed. In this systematic review examining the relationship of IBD and bariatric surgery, 28 studies were found. Overall, bariatric surgery is safe in patients with pre-existing IBD, but may increase the risk of de novo IBD development. Lay Summary We found that patients with obesity who had bariatric weight loss surgery have slightly increased risk of developing new onset inflammatory bowel disease (IBD). In patients with pre-existing IBD who underwent bariatric surgery, overall surgery was safe without worsening IBD.