Purpose: The purpose of this study was to establish estimates of incidence and fatality rates, and to identify likely etiologies of first attack acute pancreatitis (FAAP) in an urban Norwegian population.
Material and methods: A total of 874 patients were discharged with a diagnosis of acute pancreatitis from the two hospitals in this region between 1.1.1996 and 31.12.2006. Patient records were reviewed and patients with a verifiable FAAP were identified. Demographic variables, likely etiology, and outcome were registered.
Results: FAAP was verified in 567 (65%) of the patients (300 women and 267 men) with a median age of 58 years (range 7-98). The average yearly incidence rate of FAAP was 14.6/100 000 and the gender-specific incidence rates increased yearly by approx. 6% (p = 0.006). There was a decline in diagnoses by s-Amylase from approx. 90% to 62% in 2006 and an increase in diagnoses obtained by CT (p < 0.001). The case fatality rate was low (3.5%), but higher among men (5.8%) than women (2%, p = 0.037). The case fatality rate was lowest among patients with gallstones (0.7%) and higher among patients with alcohol (9%), miscellaneous (10.4%), and non-assessed etiology (6.6%) of FAAP (p < 0.05). Male gender, increasing age, and etiology (alcohol, miscellaneous causes, and non-assessed) were associated with increased case fatality rate in an adjusted regression model (p < 0.001).
Conclusions: The incidence rate of FAAP is low and differs from that of official registries. The case fatality rate is low, but related to gender, age, and likely etiology of FAAP.