Use Of Statins May Prevent Breast Cancer, Say University Of Pittsburgh Researchers

"While scientists have known for years that cholesterol inhibition serves to inhibit tumor cell growth, our analysis is one of the first to look exclusively at the relationship between lipid-lowering medications and the development of breast cancer, and our findings are dramatically positive," said study author and lead investigator Jane Cauley, Dr.P.H., professor of epidemiology at the University of Pittsburgh Graduate School of Public Health.

The Pittsburgh-led study found that older women who took statins and non-statin lipid-lowering drugs experienced a 60 to 70 percent reduction in their risk of breast cancer over approximately seven years.

Researchers reviewed data on 7,528 white women age 65 years and older who participated in the Study of Osteoporotic Fractures at sites in Pittsburgh, Baltimore, Minneapolis and Portland, and followed them for seven years.

A total of 234 (3.3%) cases of breast cancer were reported among the 6,952 participants who reported no use of lipid-lowering drugs; six cases (2.1%) among the 284 women who used statins; and four cases (1.3%) among the 292 who used nonstatin lipid-lowering drugs. The combined group of lipid-lowering drug users had a 68 percent reduction in the risk of breast cancer.

Investigators adjusted for body mass index and other risk factors for breast cancer such as the age at menarche, age at first birth, parity, physical activity and alcohol consumption. The results were essentially the same in all cases.

"There is a significant difference in the percentage of breast cancer events between women who used lipid-lowering drugs and those who did not, and these findings have important public health implications given the widespread use of these medications today," noted Dr. Cauley. "Our findings need confirmation by other, larger studies involving more women and randomized clinical trials before we can recommend therapeutic interventions to prevent breast cancer with these agents."

The hypothesis that reduction in total fat will result in a decreased risk of breast cancer is being tested in a separate study that is part of the Women's Health Initiative (WHI), an ongoing set of clinical trials involving 161,000 women, testing preventive measures for heart disease, osteoporosis and cancer of the breast and colon. Results are expected in 2006. WHI is sponsored by the National Heart, Lung and Blood Institute, one of the National Institutes of Health.

Co-investigators on the current study include other researchers from the University of Pittsburgh, the University of California San Francisco and Kaiser Permanente Center for Health Research in Portland. The study was supported by Public Health Service research grants.