Statin use and risk of pancreatic cancer: results from a large, clinic-based case-control study.

Background: Statins are cholesterol-lowering medications with pleiotropic effects, including alterations in growth signaling, as well as immunomodulatory and anti-inflammatory effects that may alter cancer risk. Evidence from previous epidemiologic studies is inconsistent about whether statin use is associated with a reduced risk of pancreatic cancer (PC).
Methods: Patients with confirmed diagnoses of PC (cases) were recruited from medical and surgical oncology clinics, with controls (frequency-matched by sex and age) recruited from general medicine clinics, at a high-volume academic medical center over a 6-year period (2006-2011). Direct interviews were conducted with an epidemiological risk factor questionnaire covering topics such as medical history, lifestyle factors, and medication usage. Adjusted multivariable logistic regression was used to compute odds ratios (ORs) and 95% confidence intervals (CIs) as estimates of the relative risk of PC.
Results: Data were obtained from 536 cases and 869 controls. Ever use of statins was associated with a 34% reduced PC risk (OR, 0.66; 95% CI, 0.47-0.92). In sex-stratified analyses, risk was statistically significantly reduced in men only (OR for men, 0.50; 95% CI, 0.32-0.79; OR for women, 0.86; 95% CI, 0.52-1.43). Duration of use was inversely associated with PC risk (>10-year use: overall OR, 0.51; OR for men, 0.41; 95% CI, 0.21-0.80; P(trend)  = .006).
Conclusions: This is the largest case-control study to demonstrate an inverse association between statin use and PC risk. Risk reduction in statin users appears to be sex-specific and is more pronounced in long-term users. Further research is warranted to better characterize this association and clarify the roles of underlying biologic mechanisms.
(© 2015 American Cancer Society.)