Statins and the risk of pancreatic cancer in Type 2 diabetic patients--A population-based cohort study

The aim of this study was to determine whether statin use exerts a protective effect against pancreatic cancer in Type 2 diabetic patients. A retrospective population-based cohort study was designed to analyze the National Health Insurance Research database (NHIRD) from 1997-2010 in Taiwan. A total of 1,140,617 patients with a first-time diagnosis of Type 2 diabetes were enrolled. The event was defined as newly diagnosed pancreatic cancer. A Cox proportional hazards regression model with time-dependent covariates was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for risk of pancreatic cancer associated with statin use in the diabetic cohort. A total of 2,341 patients with newly diagnosed pancreatic cancer were identified in the diabetic cohort during the follow-up period of 6,968,217.1 person-years. In this cohort, 450,282 patients were defined as statin users (statin use ≥ 28 cumulative defined daily dose [cDDD] in 1 year) and 0.14% had pancreatic cancer; 690,335 patients were statin nonusers (statin use <28 cDDD in 1 year) and 0.25% had pancreatic cancer. Statin use significantly decreased the risk of pancreatic cancer (adjusted HRs: 0.78 in 28-83 cDDD per year; 0.48 in 84-180 cDDD per year; and 0.33 in >180 cDDD per year) after adjusting for multiple confounders. There was a significant dose-effect of statin use for the risk of pancreatic cancer (p for trend: <0.001). Statin use may be associated with a reduced risk of pancreatic cancer in Type 2 diabetic patients. More research is needed to clarify this association.