Healthy Cholesterol Levels Could Lower Prostate Cancer Risk
While research is preliminary, the findings are encouraging, doctors say
FRIDAY, Oct. 6, 2006 (HealthDay News) -- Doctors have long known that lowering your cholesterol levels helps protect your heart. But could it also reduce the risk of prostate cancer for men?
Researchers are increasingly optimistic that the two conditions are related, making what's good for the heart good for the prostate, too.
"This is an upcoming area. There may really be something there," said Dr. William J. Catalona, director of the Clinical Prostate Cancer Program at Northwestern University's Robert H. Lurie Comprehensive Cancer Center, and the doctor who pioneered use of PSA -- prostate specific antigen -- tests for early detection of prostate cancer.
Catalona pointed to recent epidemiologic studies -- those that review health records of large numbers of people over relatively long periods of time -- that have found that men who took drugs to reduce their cholesterol levels for other health reasons also had a lower risk for prostate cancer. What's more, these studies have shown that the men who were diagnosed with prostate cancer had less risk of an aggressive form of the disease if they were on these drugs, called statins.
Elizabeth A. Platz, an associate professor in the Department of Epidemiology at Johns Hopkins Bloomberg School of Public Health, was the author of one of these studies. It followed 34,000 men for 10 years and recorded their use of statins every two years. None of the men had prostate cancer at the start of the study.
The study results, presented at the American Association for Cancer Research annual meeting last year, found that men who took statins had half the risk of advanced prostate cancer and one-third the risk of metastatic prostate cancer, compared to men who did not use the drugs.
"Directly as a result of this study of statin drugs, we are now investigating whether having higher blood cholesterol is associated with a higher future risk of prostate cancer overall," Platz said of her work, which is being done in conjunction with researchers at Harvard University. "We want to try to sort out the pathways that could affect this."
One possible explanation, Catalona said, is that cholesterol is one of the key elements in creating testosterone, a hormone that could be associated with prostate cancer risk.
"The current belief is that some variant of male hormones might promote prostate cancer growth, and [since] the main building block for male hormones is cholesterol," he said, by lowering cholesterol levels, you could be lowering excessively high testosterone levels.
But, Catalona, added, it's too soon to recommend that men take statin drugs solely to reduce their risk of prostate cancer. But if a patient is already taking these drugs to lower his risk for cardiovascular disease, this could be an added benefit.
"The common theme here is what is heart-healthy may also be prostate-healthy," he said.
The work on cholesterol and prostate cancer follows well-documented research showing that low cholesterol levels, especially LDL or "bad" cholesterol, reduces the risk for cardiovascular disease.
Since these benefits are so clear in reducing heart-disease risk, men don't need to wait until research proves a cholesterol-prostate cancer link. They should go ahead and improve their diet and lifestyle, particularly through exercise, to lower their cholesterol to healthy levels, said Mark Moyad, a University of Michigan researcher and director of Complementary and Alternative Medicine at the University of Michigan Medical Center.
For Moyad, the role of cholesterol became particularly important after a study he did found surprisingly high cholesterol levels in black men. Blacks have a 60 percent greater incidence of prostate cancer and twice the mortality rates compared to other racial and ethnic groups, according to the National Prostate Cancer Coalition. The group teamed with Moyad on the research.
Moyad found that approximately 10 percent of the 114 men in the study had high PSA test results, which was what he expected. But, 80 percent of the men also had either high or very high cholesterol levels, with LDL readings above 160 milligrams per deciliter.
"We were really surprised at the high numbers," said Moyad, who added that researchers would normally expect between 25 percent and 30 percent of the men to have high cholesterol readings. "And these were the men who were motivated enough to worry about their prostate and come in," he added.
Moyad said the high numbers "unmask the higher risk for cardiovascular disease" in the general population and suggest that screenings for specific diseases like prostate cancer should also include tests for other health-risk markers, such as cholesterol, blood pressure and body mass index.
"We shouldn't get too focused on one disease, but focus on a variety of health practices that can reduce the risk of a variety of common killers in the U.S.A.," he said.
To learn more about the health risks posed by high cholesterol, visit the American Heart Association.