Incidence, aetiology and mortality rate of acute pancreatitis over 10 years in a defined urban population in Sweden

Background: There is a wide range (5-50 per 100 000) in the reported annual incidence of acute pancreatitis. Furthermore, the predominant aetiology varies in different reports. This study was undertaken to establish the current incidence, aetiology and associated mortality rate in a defined population. Methods: A retrospective study of all cases of acute pancreatitis admitted over a 10-year period to a single institution was performed. In addition the autopsy and forensic materials were reviewed. Results: Altogether 883 attacks of acute pancreatitis were recorded, of which 547 were first attacks. The annual incidence of first attacks was 23.4 per 100 000. Including relapses, the incidence was 38.2 per 100 000. Biliary disease was the main aetiological factor in first attacks whereas alcohol was the predominant factor when relapses were included. The mean annual mortality rate for acute pancreatitis in the population was 1.3 per 100 000. Of 31 patients who died from acute pancreatitis only 15 were diagnosed before death. For recurrent disease the mortality rate was 0.3 per cent. In 12 patients the pancreatitis was associated with pancreatic carcinoma. Conclusion: It is important to differentiate between first attacks and relapses, since both incidence and aetiology figures are influenced by this, and it is important to include autopsy and forensic material in population-based mortality studies.