Obesity Increases the Severity of Acute Pancreatitis

Abstract

Purpose: Obese patients appear to be at risk for more severe complications of acute pancreatitis (AP). APACHE-O score has been suggested to improve APACHE-II accuracy in predicting severe outcome in AP by adding a numerical score for obesity. Aims: (A) To determine if APACHE-O adds any significant predictive value to APACHE-II score and (B) to test the hypothesis that obese patients are at risk of more severe complications of AP than non-obese patients because of a more intense inflammatory response to pancreatic injury. Methods: 102 AP patients (mean age 50 years; 52 females, 50 males) were prospectively studied. Using a Body Mass Index (BMI) >30, 28% of the subjects were obese. Nineteen patients (19%) developed organ dysfunction and were classified as having severe AP (SAP). Receiver operating curves for prediction of SAP were calculated using admission APACHE-II and APACHE-O scores. Binary logistic regression was performed to assess if obesity is a risk for SAP and to determine the clinical factors associated with severe disease. Serum levels of IL-6, MCP-1 (early markers) and CRP and Ranson's scores (later markers) were compared between obese and non-obese patients with AP. Results: Admission APACHE-O (AUC: 0.895) and APACHE-II (AUC: 0.893) showed similar accuracy in predicting severe outcome. Admission APACHE-O cut-off value of 9 showed a sensitivity of 84%, specificity 82%, positive predictive value 52%, negative predictive value 96% and accuracy 83%. BMI was identified as a significant risk for SAP (OR: 2.8, p = 0.048). CRP levels and Ranson's score were significantly higher in obese than non-obese patients with AP (p = 0.0001 and p = 0.021 respectively). Admission IL-6 and MCP-1 levels showed a trend toward higher levels in obese patients but did not reach statistical significance (p = 0.368 and p = 0.325 respectively). Conclusions: Obesity is an independent risk for severe acute pancreatitis. Admission APACHE-O score is not more accurate than APACHE-II. Our study results suggest that obesity increases the severity of AP by amplifying the inflammatory response to injury. [figure 1]Figure