450 Obesity is an Independent Risk Factor for Post-ERCP Pancreatitis: Results of a Nationwide Database Analysis

450 Obesity is an Independent Risk Factor for Post-ERCP Pancreatitis: Results of a Nationwide Database Analysis Nitin Kumar*, Marwan Abou Gergi, Christopher C. Thompson Division of Gastroenterology, Brigham & Women’s Hospital, Boston, MA; Harvard Medical School, Boston, MA Background: Pancreatitis is the most common complication of endoscopic retrograde cholangiopancreatography (ERCP) with a reported incidence rate of 4-6%. Previous studies have identified multiple patient-related risk factors for post-ERCP pancreatitis, however variable results have been reported concerning diabetes. No studies have identified obesity or other components of metabolic syndrome as independent risk factors. Aim: To determine whether obesity, hyperlipidemia, and diabetes are independent predictors of post-ERCP pancreatitis. Methods: This was a retrospective cohort study using the 2009 Nationwide Inpatient Sample (NIS) database, the largest inpatient database in the US. The NIS contained information from 39 million discharges. Discharges were included in this study if they had an ICD9 procedure code indicating ERCP and were excluded if they had a primary or secondary ICD9 code for sepsis, cholangitis, choledocholithiasis or if age was less than 18. The primary outcome was acute pancreatitis. Exposures of interest were diabetes, hyperlipidemia, hypertension, and obesity (BMI 30). Crude and adjusted odds ratios were calculated using univariate and multivariable regression analyses. The set of potential confounders included in the multivariable regression models included: age, sex, race, admission type (elective vs urgent/emergent), number of comorbidities, median income in the patient’s zip code, hospital location (rural vs. urban), region (Northeast, Midwest, West, or South), teaching status, and size. Since chronic pancreatitis, alcohol abuse, and certain medications are related to pancreatitis, we performed a sensitivity analysis by further controlling for those conditions. As NIS does not capture medications, we included diseases frequently associated with them: AIDS, congestive heart failure, metastatic cancer, lymphoma, rheumatoid arthritis, depression, and psychosis. Results: 25,641 discharges were eligible for the study, of which 22% had diabetes, 24% had hyperlipidemia, and 10% had obesity. The overall post-ERCP pancreatitis rate was 5.5%. On univariate analysis of these factors, obesity and hyperlipidemia were predictors of post-ERCP pancreatitis. After adjusting for the defined set of potential confounders and established risk factors, obesity diabetes, and hyperlipidemia were each independent predictors of post-ERCP pancreatitis. In the final model that controlled for the defined set of potential confounders, obesity, diabetes, and hyperlipidemia, remained independent predictors of post-ERCP pancreatitis. Sensitivity analysis did not alter these results. All analyses are displayed in Table 1. Conclusions: Obesity is an independent risk factor for post-ERCP pancreatitis. Additionally, this study confirms the findings of smaller series that suggest diabetes and hyperlipidemia are independent predictors of post-ERCP pancreatitis.