Risk Factors for Post‐Endoscopic Retrograde Cholangiopancreatography Pancreatitis in Patients With Post‐Endoscopic Sphincterotomy Papillae

ABSTRACT Objectives Post‐endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) is a well‐known complication. While most reported risk factors relate to treatment‐naïve papillae, those in patients with post‐endoscopic sphincterotomy (post‐EST) papillae remain unclear. We aimed to identify risk factors for PEP in patients with a history of EST undergoing ERCP for biliary disease. Methods We retrospectively analyzed 678 patients with prior EST who underwent ERCP between January 2017 and October 2023. PEP was diagnosed according to established criteria. Logistic regression analyses were performed to identify risk factors. To account for repeated ERCP sessions, additional analyses using cluster‐robust standard errors were conducted. Body mass index (BMI) was evaluated as both a continuous variable and according to World Health Organization categories. Prophylactic rectal diclofenac or intravenous nafamostat mesilate was administered at the operator's discretion. Results The mean age was 75.4 years, and PEP occurred in 4.4%. Multivariate analysis identified female sex ( p = 0.016; odds ratio OR 2.97), low BMI ( p = 0.021; OR 2.94), and prolonged procedure time ( p = 0.0048; OR 4.29) as independent risk factors. Operator experience and prophylactic agents were not significantly associated with PEP. In analyses accounting for within‐patient correlation, BMI <18.5 kg/m 2 remained significantly associated with PEP (OR 2.73; p = 0.012), whereas associations with sex and procedure duration were attenuated. Conclusions Low BMI is a consistent risk factor for PEP in patients with post‐EST papillae. The effectiveness of pharmacologic prophylaxis may differ from that in treatment‐naïve papillae and warrants prospective evaluation. Trial Registration N/A.