Can Statins Help to Reduce Cancer Deaths?

People with elevated cholesterol levels take statins to ward off heart attacks and strokes—and a report in the New England Journal of Medicine suggests that the drugs may reduce mortality from cancer, although experts caution that more data are needed before statins can be prescribed for this indication.

“The findings are exciting, but there are also major gaps in the analysis,” says Neil Caporaso, MD, chief of the Genetic Epidemiology Branch at the National Cancer Institute (NCI), who was not involved in the research. “We need follow-up studies and additional confirmation.”

Cancerous or otherwise, all cells depend on cholesterol for membrane integrity, signaling, protein synthesis, and other functions. Studies have suggested that statins, which block cholesterol production, may interfere with cancer cell proliferation and migration. In the current work, researchers from Copenhagen University Hospital and the University of Copenhagen in Denmark combed through cancer incidence data gathered by the country's civil registration system, which tracks mortality by disease, drug prescriptions, and many other variables for the country's entire population.

Analyzing patient data from 1995 to 2007, the researchers found that statin use initiated before a cancer diagnosis was associated with a 15% decrease in both cancer mortality and death from any cause.

Although the data were complete with respect to gender, cancer stage at diagnosis, diagnosis of cardiovascular disease and diabetes before cancer, race, and ethnic descent, they were lacking in other important covariates, such as smoking and screening for early tumor detection.

Caporaso, who wrote an accompanying editorial, says these shortcomings can be addressed by scouring of other data sources, including national health care providers such as Kaiser Healthcare, observational studies, and clinical trials.

He singles out the Atherosclerosis Risk in Communities Study (sponsored by the National Heart, Lung and Blood Institute) as an example of a promising source of data. Launched in 1987, this observational study tracks nearly 16,000 individuals. “They build in clinical cholesterol measurements and genetic data, so you can ask if there's a particular gene variant that affects statin performance as an effect modifier for cancer mortality,” Caporaso says.

“If statins do have an impact on cancer mortality, then we want to understand that mechanism really well so we can think about how to exploit it for prevention or therapy,” he adds. For example, mechanistic data might generate insights about whether statins can prevent cancer at doses lower than those employed for cardiovascular indications, which can elevate risks for diabetes.

“Cohorts and existing trials might be able to show whether benefits are substantial and persist over decades,” comments Sholom Wacholder, PhD, a biostatistician in the NCI's Division of Cancer Epidemiology and Genetics. “We could be looking at a real advance in public health. We just don't know yet.”