JACC: Statin use not linked to cancer, based on EMR data
Statins, a drug class administered to patients as an attempt to foil cardiovascular events, was not linked to an increased risk of cancer, according to the results of a retrospective analysis of more than 45,000 patients. The study, published in the July 26 issue of the Journal of the American College of Cardiology, may provide answers to the ongoing debate as to whether or not statins are linked to cancer.

“Statins (or 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) are among the most prescribed drugs in the U.S. for the management of dyslipidemia, atherosclerosis, and cardiovascular event risk reduction,” Claudio Marelli, MD, of S2 Statistical Solutions in Cincinnati, and colleagues wrote. After the JUPITER study was published, debate has surrounded whether or not statin indications should be expanded for lower risk individuals. However, there is an unsettled debate surrounding whether statins could be associated with cancer.

To study the possible link between cancer and statin use, Marelli and colleagues conducted a retrospective cohort analysis using more than 11 million patient records from January 1990 through February 2009 from GE Healthcare's Centricity EMR database. The researchers used propensity matching to find pairs of patients receiving and not receiving statin therapy; 45,857 patients were included in the study.

The diagnosis of any type of cancer recorded in the EMR before medication was used as the study’s primary endpoint. The patients included in the study had an average time in the database of approximately eight years. The average follow-up interval after time zero for patients administered a statin were 4.7 years and 4.6 years for matched patients not taking statins.

The researchers reported that the incidence of cancer in patients administered statin therapy decreased to 11.37 percent compared with 11.11 percent in matched patients not taking statins. A Cox regression analysis showed a nonsignificant hazard ratio of 1.04 and Kaplan-Meier curves for the diagnosis of any cancer up to 10 years showed no difference for patients taking a statin and those not taking statins.

Marelli and colleagues reported that the study revealed “no statistically significant association of statins with cancer.” They wrote that the results are consistent “with the fact that a plausible biological mechanism to implicate statins as causative agents in cancer has never been demonstrated.

“In fact, numerous preclinical studies have supported the potential anticancer activity of these compounds, providing evidence of their antiproliferative, proapoptotic, anti-invasive, and radiosensitizing properties,” the authors wrote. Additionally, the authors noted that if statins were associated to cancer, they would have seen an increase in at least one type of cancer.

The authors cautioned that a potential limitation of the study could be due to the fact that propensity scoring methods may not completely eliminate bias that’s due to unmeasured or hidden covariates.

“This EMR database analysis of more than 91,000 U.S. adults with complete clinical datasets who were propensity matched with an average of 4.6 years of follow-up, demonstrated no statistically significant increased risk of cancer associated with statins,” the authors concluded.