To Örebro University

BACKGROUND: Obesity is increasing among patients with inflammatory bowel disease, but bariatric surgery has been rare in this group owing to concerns about worsening the inflammatory bowel disease. The aim of the study was to evaluate inflammatory bowel disease-related outcomes following bariatric surgery.

METHODS: Nationwide cohort of all adult patients in Sweden between 2007 and 2020 with obesity and inflammatory bowel disease. Patients were matched 1 : 1 with a two-stage matching process between those undergoing bariatric surgery with those who did not (classified by inflammatory bowel disease subtype followed by a propensity score match including sex, age, number of previous targeted therapies, presence of immunotherapy, cumulative oral corticosteroid dose, and previous intestinal surgery). The primary composite outcome comprised inflammatory bowel disease-related hospitalization, initiation of corticosteroid therapy, immunomodulation, commencement of a new targeted therapy or major inflammatory bowel disease-related surgery.

RESULTS: The study included 798 patients with inflammatory bowel disease and obesity: 399 who underwent bariatric surgery (145 Crohn's disease, 238 ulcerative colitis, 16 unclassified inflammatory bowel disease) versus 399 who did not. Over a median observation period of 3.3 years in the surgery group and 3.0 years in the non-surgery group, the composite primary endpoint occurred in 201 patients who had surgery (incidence rate 11.9 (95% confidence interval (c.i.) 10.2 to 13.5) per 100 person-years) and 226 without surgery (incidence rate 15.1 (13.1 to 17.0) per 100 person-years), corresponding to an adjusted hazard ratio of 0.66 (95% c.i. 0.51 to 0.85) in those undergoing bariatric surgery compared with those who did not.

CONCLUSION: Bariatric surgery was associated with improved inflammatory bowel disease-related outcomes among patients with inflammatory bowel disease and obesity, suggesting a potential benefit from bariatric surgery among patients with concomitant obesity and inflammatory bowel disease.