Statins use and risk of breast cancer recurrence and death: A systematic review and meta-analysis of observational studies

Purpose. Statins are widely prescribed drugs for lowering cholesterol. Some studies have suggested that statins can prevent breast cancer recurrence and reduce mortality rate. However they are not conclusive. Present systematic review and meta-analysis of published cohort studies was conducted to determine the effects of statins intake and risk of breast cancer recurrence and mortality rate. Methods. Online databases (PubMed, Embase, Scopus, EBSCO and Cochrane Collaboration) were searched through October 2014. Pooled relative risks and 95% confidence intervals were calculated with random-effects. Results. A total of 8 cohort studies (4 for recurrence 2 for mortality and 2 for both) involving 124669 participants with breast cancer were eligible. Our results suggest a significant reduction in recurrence (OR= 0.79. I²= 38%) and death (OR = 0.84, I² = 8.58%) among statin users. Conclusion. Our meta-analysis suggests that breast cancer patients will benefit from statin intake, however from these cohorts we are unable to differentiate between various statins in terms of effectiveness and duration of use. We highly propose conducting randomized clinical trials.