S902 Is Bariatric Surgery a Risk Factor for De Novo IBD Development? A Meta-Analysis

Abstract

Introduction: The incidence of obesity has been steadily increasing across the globe and many are turning to bariatric surgery (BS) as an effective treatment. The surgeries, however, are associated with both morbidity and mortality. Recently, studies seem to suggest an association between the risk of developing de-novo inflammatory bowel disease (IBD) in patients who underwent BS. This meta-analysis reports on the pooled outcomes of de-novo IBD development in post-BS patients. Methods: A comprehensive search of several databases was conducted including PubMed, Embase, and ScienceDirect, to identify studies investigating de-novo IBD development in post-BS patients. Standard meta-analysis methods and random effects models were used to calculate the pooled odds-ratio (OR) and mean-difference (MD) with corresponding 95% confidence intervals (CI). I2% statistics was used to assess the heterogeneity. (Figure) Results: Six studies were included that reported on 142,406 patients that underwent BS. The average reported BMI at time of BS was greater than 45 and average reported age at time of BS was less than 40 years old. The pooled rate of de-novo Crohn’s disease (CD), Ulcerative Colitis (UC), and unspecified IBD in patients undergoing BS was 4% (95% CI 1.3-11.7, I2=99%), 0.9% (95% CI 0.4-1.8, I2=95%), and 0.6% (85% CI 0.1-6.1, I2=91%) respectively. The majority of those who developed de-novo IBD were females (74%) and CD (52%) was the most common subtype. (Table) Conclusion: The results of our meta-analysis indicate an association between BS and de-novo IBD development, especially CD. It has been hypothesized that changes in the intestinal microbiome after bariatric surgery trigger immune responses that lead to the development of IBD in genetically susceptible individuals. However, some have suggested that these findings may be due to the association between IBD and obesity, by unknown mechanism. Additional research is needed to further validate our findings.Figure 1.: Forest plot Table 1. - Summary of pooled rates De-novo IBD in patients after bariatric surgery Pooled rates (95% confidence interval, I2 heterogeneity) Ulcerative colitis 0.9% (0.4-1.8, 95%) Crohn’s disease 4% (1.3-11.7, 99%) Unspecified IBD 0.6% (0.1-6.1, 91%)