Statins reduce the risk of pancreatic cancer in humans - A case-control study of half a million veterans

Objective: Statins are commonly used cholesterol-lowering agents that are noted to suppress tumor cell growth in several in vitro and animal models. Methods: We studied the association between pancreatic cancer and statins in veterans. A retrospective, nested case-control study was conducted using prospectively collected data from the Veterans Integrated Service Networks 16 Veteran Affairs database from 1998 to 2004. We analyzed data on 483,733 patients from 8 states located in south central United States. The primary variables of interest were pancreatic cancer and the use of statins before the diagnosis of pancreatic cancer. Multiple logistic regression analysis was done to adjust for covariates including age, sex, body mass index, smoking, diabetes, and race. The SAS software was used for statistical computing. Results: Of the 483,733 patients in the study, 163,467 (33.79%) were on statins, and 475 (0.098%) patients had a primary diagnosis of pancreatic cancer. Stalin use of more than 6 months was associated with a risk reduction of pancreatic cancer of 67% (adjusted odds ratio, 0.33; 95% confidence interval, 0.26-0.41; P < 0.01). A dose-response relationship was noted between statin use and pancreatic cancer with an 80% risk reduction (adjusted odds ratio, 0.2-1 95% confidence interval, 0.13-0.29; P < 0.01) with use of statin for more than 4 years. Furthermore, the protective effect of statin was seen across different age and racial groups, and was irrespective of the presence of diabetes, smoking, or alcohol use. Conclusions: Statins seem to be protective against the development of pancreatic cancer, and the magnitude of the effect correlates with the duration of statin use.