Association Between Statins and the Risk of Kidney Cancer Incidence and Mortality Using the Korean National Health Insurance Claims Database

Background Conflicting results have been reported regarding the potential preventive effects of statins on the risk of cancer. This study investigated the associations of statin use with the incidence and mortality of kidney cancer in South Korea. Methods In this retrospective population-based cohort study using the National Health Insurance claims database, we compared patients aged 45-70 years who had used statins for at least 6 months to non-statin users matched by age and sex from 2005 to June 2013. The main outcomes were kidney cancer incidence and mortality according to statin use. Cox proportional hazard regression was used to calculate the adjusted hazard ratios (aHRs) and 95% confidence intervals (95% CIs). Results In the cohort of 1 008 101 people, the aHRs for the association between statin use and the outcomes were .84 (95% CI: 0.71-.99) for kidney cancer incidence and .65 (95% CI: 0.41-.98) for kidney cancer mortality. In the matched cohort of 337 578, the risk per 1000 people of cancer incidence and mortality was 1.63, 1.07, and .24, .17 in statin users and non-users, respectively. In matched cohort, the risk of kidney cancer incidence and mortality decreased, but it is not statistically significant. Also, there was no linear relationship with increased doses. Conclusion Statin use might be associated with a decreased risk of kidney cancer incidence and mortality, but it showed no statistical significance. This study was a large-scale analysis, however, further studies that are larger and multinational in scope are needed to confirm the beneficial effects of statins on survival.