Cholecystectomy and sphincterotomy in patients with mild acute biliary pancreatitis in Sweden 1988 - 2003: a nationwide register study

BACKGROUND: Gallstones represent the most common cause of acute pancreatitis in Sweden. Epidemiological data concerning timing of cholecystectomy and sphincterotomy in patients with first attack of mild acute biliary pancreatitis (MABP) are scarce. Our aim was to analyse readmissions for biliary disease, cholecystectomy within one year, and mortality within 90 days of index admission for MABP. METHODS: Hospital discharge and death certificate data were linked for patients with first attack acute pancreatitis in Sweden 1988-2003. Mortality was calculated as case fatality rate (CFR) and standardized mortality ratio (SMR). MABP was defined as acute pancreatitis of biliary aetiology without mortality during an index stay of 10 days or shorter. Patients were analysed according to four different treatment policies: Cholecystectomy during index stay (group 1), no cholecystectomy during index stay but within 30 days of index admission (group 2), sphincterotomy but not cholecystectomy within 30 days of index admission (group 3), and neither cholecystectomy nor sphincterotomy within 30 days of index admission (group 4). RESULTS: Of 11636 patients with acute biliary pancreatitis, 8631 patients (74%) met the criteria for MABP. After exclusion of those with cholecystectomy or sphincterotomy during the year before index admission (N = 212), 8419 patients with MABP remained for analysis. Patients in group 1 and 2 were significantly younger than patients in group 3 and 4. Length of index stay differed significantly between the groups, from 4 (3-6) days, (representing median, 25 and 75 percentiles) in group 2 to 7 (5-8) days in groups 1. In group 1, 4.9% of patients were readmitted at least once for biliary disease within one year after index admission, compared to 100% in group 2, 62.5% in group 3, and 76.3% in group 4. One year after index admission, 30.8% of patients in group 3 and 47.7% of patients in group 4 had undergone cholecystectomy. SMR did not differ between the four groups. CONCLUSION: Cholecystectomy during index stay slightly prolongs this stay, but drastically reduces readmissions for biliary indications.