Incidence, Prevalence, and Survival of Chronic Pancreatitis: A Population-Based Study

Abstract

Population-based data on chronic pancreatitis (CP) in the United States are scarce. We determined incidence, prevalence, and survival of CP in Olmsted County, MN. Using Mayo Clinic Rochester's Medical Diagnostic Index followed by a detailed chart review, we identified 106 incident CP cases from 1977 to 2006 (89 clinical cases, 17 diagnosed only at autopsy); CP was defined by previously published Mayo Clinic criteria. We calculated age- and sex-adjusted incidence (for each decade) and prevalence rate (1 January 2006) per 100,000 population (adjusted to 2000 US White population). We compared the observed survival rate for patients with expected survival for age- and sex-matched Minnesota White population. Median age at diagnosis of CP was 58 years, 56% were male, and 51% had alcoholic CP. The overall (clinical cases or diagnosed only at autopsy) age- and sex-adjusted incidence was 4.05/100,000 person-years (95% confidence interval (CI) 3.27-4.83). The incidence rate for clinical cases increased significantly from 2.94/100,000 during 1977-1986 to 4.35/100,000 person-years during 1997-2006 (P<0.05) because of an increase in the incidence of alcoholic CP. There were 51 prevalent CP cases on 1 January 2006 (57% male, 53% alcoholic). The age- and sex-adjusted prevalence rate per 100,000 population was 41.76 (95% CI 30.21-53.32). At last follow-up, 50 patients were alive. Survival among CP patients was significantly lower than age- and sex-specific expected survival in Minnesota White population (P<0.001). Incidence and prevalence of CP are low, and ∼50% are alcohol related. The incidence of CP cases diagnosed during life is increasing. Survival of CP patients is lower than in the Minnesota White population.