Case-fatality from acute pancreatitis is decreasing but its population mortality shows little change

Abstract

Background/objectives: The reasons for changing epidemiology of acute pancreatitis (AP) are poorly defined. We hypothesized that trends for severity, case-fatality and population mortality from AP will provide an insight into the rising burden of AP in the population. We evaluated trends in the hospitalizations, case-fatality, severity and population mortality related to AP in the US population.

Study: We used the National Hospital Discharge Survey to calculate age, sex and race standardized hospitalizations of and case-fatality rates for AP, and Vital Statistics to calculate AP-related population mortality from 1983 to 2010, using 2010 US census as the reference.

Results: Number of discharges per 100,000 population with primary diagnosis of AP increased 2 times from 42.4 (95% CI 38.2-46.5) during 1983-1986 to 85.4 (95% CI 62.8-108.1) during 2007-2010. During corresponding intervals, case-fatality from AP decreased 62% from 2.02% (95% CI 2.01-2.04) to 0.79% (95% CI 0.78-0.80), but population mortality per million population due to AP as primary cause remained stable from 9.28 (95% CI 8.94-9.62) to 9.91 (95% CI 9.56-10.26), and from AP as any cause decreased significantly (but only 12%) from 20.87 (95% CI 20.36-21.38) to 18.48 (95% CI 18.00-18.96). Prevalence of severe AP increased from 5% (95% CI 4.95-5.05%) during 1991-1994 to 9.78% (95% CI 9.73-9.83%) during 2007-2010.

Conclusion: An increasing prevalence of severe disease suggests true population increase to be an important contributor to the rising incidence of AP. A lack of proportional increase in population mortality suggests the impact of medical advances in the evaluation and management of AP.

Keywords: Epidemiology; Incidence; Mortality; Pancreatitis; Severity; Trend.