January 3, 2006
Statins do not affect cancer risk, researchers say
By Andrew Stern
CHICAGO (Reuters) - Statin drugs are proven to lower
cholesterol levels and reduce the risk of heart attacks, but
researchers said on Tuesday the best-selling medications do not
ward off cancer as some earlier studies have suggested.
Preliminary studies showed lower rates of breast, prostate
and colon cancers among statin users. But an analysis of 26
studies involving 87,000 patients concluded the drugs had no
impact on cancer rates, according to their report published in
the Journal of the American Medical Association.
"When we put all the trials together we were hopeful of
validating a cancer-protective effect, but we ended up not
finding any," study author Michael White of the University of
Connecticut and Hartford Hospital said in a telephone
Another study, by the American Cancer Society, reviewed
data on more than 130,000 patients in the United States and
found no effect on colon cancer rates between those who used
statins and those who did not.
Their findings were published in the Journal of the
National Cancer Institute's January 4 issue.
Statins, the most prescribed drugs in the world, include
Pfizer Inc.'s Lipitor, Merck & Co Inc.'s Zocor, Bristol-Myers
Squibb's Pravachol, Merck's Mevacor and Novartis AG's Lescol.
'IT'S COME FULL CIRCLE'
White said studies that found a link between statin use and
protection against cancer checked databases of patients with or
without cancer, then looked backward for statin use.
These so-called case-controlled studies do not prove
anything, he said.
In contrast, his team dug into data from randomized studies
where patients were recruited and divided into groups to be
given statins or a placebo to measure effectiveness against
heart disease. The studies also tracked cancer cases because of
early concerns that statins might cause or promote cancer.
"It's come full circle -- first they thought it was a great
drug for heart disease that might cause cancer, then they
thought it might prevent cancer. But we now know they can take
the drug safely without risk of cancer," White said.
The analysis also looked at particular statin drugs and
different kinds of cancers to see if there were any
relationships. It found none.
"We don't want to dilute the positives from statins ... but
if you don't have heart disease and take them to prevent
cancer, that's not a good reason," White said.
In the American Cancer Society study, researchers analyzed
information from patients in a larger cancer prevention study
that began in 1992.
Patients were later asked about their use of
cholesterol-lowering drugs as well as if they had been
diagnosed with colon cancer. Cancer cases were also matched
through a government database.
Lead author Eric Jacobs, an epidemiologist for the cancer
research and advocacy group, said that approach allowed them to
look at more long-term data that still found statins had no
effect on cancer risk.
Jacobs added that other researchers will probably continue
to investigate a possible link, but "it's not especially
(Additional reporting by Susan Heavey in Washington)