Are health related outcomes in acute pancreatitis improving? An analysis of national trends in the U.S. from 1997 to 2003.

CONTEXT Acute pancreatitis is a common inflammatory disorder of the pancreas. Within the past decade our ability to diagnose and treat complications of acute pancreatitis has improved. Despite advances in diagnostic and therapeutic technology it is unclear whether we have been able to impact health related outcomes of acute pancreatitis such as incidence and mortality. OBJECTIVE The aim of this study was to use a national database of U.S. hospitals to evaluate the trends in the incidence and mortality associated with acute pancreatitis. We also examined the impact that patient demographic and hospital characteristics have on health related outcomes in acute pancreatitis. METHODS We analyzed the National Inpatient Sample Database (NIS) for all subjects in which acute pancreatitis (ICD-9 code: 577.0) was the principal discharge diagnosis during the period from 1997-2003. All identified subjects were analyzed for demographic characteristics as well as hospital characteristics. MAIN OUTCOME MEASURES The mean frequency of discharges for acute pancreatitis, percentage mortality and mean length of stay for acute pancreatitis were determined for all identified cases. STATISTICS The statistical significance of the difference in the discharge frequency, mortality and length of stay over the study period was determined by utilization of the chi-square test for trend and the linear regression. RESULTS During the study period there were 1,476,498 admissions with a principal discharge diagnosis of acute pancreatitis. The frequency of discharges with acute pancreatitis increased by 30.2% (P<0.001) during the period from 1997-2003. The average mortality associated with acute pancreatitis decreased by 35.2% (P<0.001) and the median length of stay decreased by 9.4% (P=0.002). Most discharges with acute pancreatitis were in the Southern U.S. and were at large non-teaching hospitals located in urban areas. DISCUSSION Possible explanations for the results of our study are the improvements in our ability to diagnose acute pancreatitis, an increase in the availability of medical ICU's and an increase in hospital admissions for gallstones and alcohol use during the study period.