The impact of bariatric surgery on admissions for gastrointestinal complications and conditions associated with obesity: A nationwide study.

Background: Obesity worsens various gastrointestinal pathologies. While bariatric surgery ameliorates obesity, it substantially modifies the gastrointestinal system depending on surgery type, with limited data on subsequent impact on obesity-related gastrointestinal admissions.
Methods: Using the 2012-2014 Nationwide Readmission Database, we included individuals with obesity who received vertical sleeve gastrectomy (VSG), Roux-en-Y gastric bypass (RYGB), or hernia repair (HR-control surgery). Our main focus was the adjusted odds ratio (aOR) for gastrointestinal inpatient admissions within 6 months following surgery compared to the 6 months preceding it, while controlling for several confounding factors. Gastrointestinal admissions were grouped into postoperative complications or obesity-associated gastrointestinal conditions.
Results: Our cohort included 140,103 adults with RYGB, 132,253 with VSG, and 12,436 HR controls. Postoperative gastrointestinal complications were most common after RYGB, prominently obstruction (aOR = 33.17, 95%CI: 18.01, 61.10), and Clostridium difficile infection (aOR: 12.52, 95%CI: 6.22, 25.19). VSG also saw significantly increased but less frequent similar conditions. Notably, for gastrointestinal conditions associated with obesity, acute pancreatitis risk was higher post-VSG (aOR = 6.26, 95%CI: 4.02, 9.73). Post-RYGB patients were most likely to be admitted for cholelithiasis with cholecystitis (aOR: 4.15, 95% CI: 3.24, 5.31), followed by chronic liver disease (aOR: 3.00, 95% CI: 2.33, 3.87). The risk of noninfectious colitis admissions was threefold higher after RYGB and VSG. No gastrointestinal conditions showed an increase after HR.
Conclusion: Despite weight loss, bariatric surgery was associated with an increased risk of hepato-pancreatobiliary and colitis admissions related to obesity in the first six postoperative months, with considerable variations in rates of gastrointestinal conditions by surgery type.
(© 2023 International Society of Surgery/Société Internationale de Chirurgie (ISS/SIC).)