S0099 Calendar Year Readmission Rates Associated With Different Etiologies of Acute Pancreatitis and Its Impact on Outcomes

INTRODUCTION: We sought to determine the 11-month readmission rate (RR) for various etiologies of AP after an initial episode of AP; and compare the outcomes and healthcare resource utilization associated with each of them. METHODS: Retrospective cohort study using the 2016 National Readmission Database (NRD). Inclusion criteria were: principal diagnosis of AP and admission in January 2016. All readmissions to any hospital for a principal diagnosis of AP within 11 months of the index admission were recorded for each patient. Patients were divided into 5 groups based on etiology of AP and primary outcome was the 11-month RR of AP. Secondary outcomes were: number of readmissions per year in each group, index admission and calendar year mortality, treatment/management variations in each group and healthcare resource utilization. RESULTS: 22,472 patients hospitalized with AP in January 2016 were included. Common etiologies were biliary (16.7%), alcohol (24.1%), drug-induced (1.6%), other (54.5%) and idiopathic (3.2%). The mean age was 53 years and 41.6% were males. The 11-month RRs for biliary, alcoholic, drug-induced, other and idiopathic AP were 7.6%, 36.2%, 10.7%, 23% and 23.7%, respectively. Over 6% of patients with alcohol-induced AP and 9.3% of patients with drug-related AP had >5 readmissions in the 11-month follow-up period [Figure 1]. Index admission mortality was highest in biliary pancreatitis (1%), while the calendar year mortality was higher in patients with other etiologies of AP (1.8%). Rates of percutaneous drainage were highest in patients with biliary AP (4.9%); while patients with idiopathic pancreatitis underwent the highest number of necrosectomies (0.5%) and had the highest need for TPN (1.5%). Patients with alcohol-induced AP had the highest rates of feeding tube placement (0.6%). Healthcare resource utilization was the highest in readmitted patients with alcohol-induced and other etiologies of AP as compared to biliary, idiopathic and drug-induced AP. Total hospital days associated with alcohol-induced AP related readmissions were 16,012 days with total healthcare costs of $114 million, while total hospital days with other AP were 25,578 days and total healthcare costs of $178 million [Figure 2]. CONCLUSION: Our study provides national data on the calendar year RR of patients with AP across different etiologies, and the impact on outcomes related to readmission. The highest RR are associated with alcohol induced AP with a significant impact on healthcare resource utilization.Figure 1.: Clinical outcomes associated with various etiologies of acute pancreatitis.Figure 2.: Healthcare Utilization Measures.