Statins may be associated with reduced cancer-related mortality

Statins may be associated with reduced cancer-related mortality, a new study has found.

Researchers from Denmark examined national data on mortality among patients who were diagnosed with cancer between 1995 and 2007 and were followed until date of death or Dec. 31, 2009. The objective of the study was to determine whether statin use started before a diagnosis of cancer was associated with better cancer-related mortality. Mortality among patients who had taken statins before diagnosis (n=18,721) was compared with mortality among those who had not (n=277,204). The study results appeared in the Nov. 8 New England Journal of Medicine.

The study involved 1,072,503 person-years of follow-up, during which 162,067 patients died of cancer, 14,489 died of cardiovascular causes, and 19,038 died of other causes. Overall, patients who had used statins had multivariable-adjusted hazard ratios of 0.85 (95% CI, 0.83 to 0.87) for death from any cause and 0.85 (95% CI, 0.82 to 0.87) for death from cancer compared with patients who had not used statins.

The researchers also assessed the relationship by recommended defined daily statin dose, or the assumed average maintenance dose per day. When this variable was considered, the adjusted hazard ratios for death from any cause and death from cancer were 0.82 and 0.83 for a defined dose of 0.01 to 0.75 per day, 0.87 and 0.87 for a defined dose of 0.76 to 1.50 per day, and 0.87 and 0.87 for a defined dose above 1.50 per day. Statin use was associated with lower cancer-related mortality in patients with 13 of 27 types of cancer. For the remaining 14 types, the confidence intervals for the multivariable-adjusted hazard ratios overlapped 1.

The authors noted that the available data on cancer characteristics such as size and metastasis were incomplete and that statin use before diagnosis could have indicated higher health awareness, among other potential limitations. However, they concluded that statin use at cancer diagnosis was associated with up to a 15% reduction in risk for cancer-related death. They called for clinical trials to determine whether statin use improves survival in cancer patients.

An accompanying editorial called for caution in interpreting the study results and suggested additional research examining existing statin trials before clinical trials are performed. The editorialist also suggested that population studies verifying the current findings and basic science studies looking at statins' mechanisms of action should be performed.

“Clinicians want to understand whether the cardiovascular and cancer effects of statins are due to overlapping or independent mechanisms, how the effects differ according to the individual agent and dose or are mediated by genes, and whether the effects correlate with the degree of lipid lowering,” he wrote.