Canadian researchers say findings aren't proof, call for more studies
TUESDAY, Nov. 5, 2013 (HealthDay News) -- Prostate cancer patients who take the cholesterol-lowering drugs known as statins appear to face a lower risk of death from their disease, new Canadian research suggests.
The decreased risk was strongest for those who were taking the statins before their cancer diagnosis, investigators found. In addition, the study also showed, statin use was associated with a lower risk for any cause of death.
Despite the evidence, however, the study team called for more research to confirm the findings.
"The results of our study suggest that the use of statins is associated with a decreased risk of prostate cancer mortality," said study co-author Laurent Azoulay, from Jewish General Hospital and McGill University in Montreal. "(But) overall, while our results are very promising, we believe that additional rigorous studies are needed before prescribing these agents to men with prostate cancer."
Azoulay and his colleagues, whose study is published online ahead of print in the Journal of Clinical Oncology, noted that they did not show a direct cause-and-effect relationship between the popular drugs taken by millions to prevent heart disease and a lower death risk from prostate cancer.
To explore the protective potential of statins, which are sold under such brand names as Zocor, Crestor and Lipitor, the authors analyzed data on almost 12,000 men from the United Kingdom who had been diagnosed with prostate cancer at some point between 1998 and 2009.
The men were tracked through 2012, for an average of more than four years after their diagnosis. During that time, nearly 3,500 died, and almost 1,800 of those deaths were attributed to prostate cancer.
Ultimately, Azoulay's team concluded that statin use was associated with both a lower risk of dying from prostate cancer as well as a lower risk of death from any cause. The protective effect attributed to statin use was strongest among those men who had begun using statins before they were diagnosed with prostate cancer.
At this point, the authors can only theorize on what the connection could be.
"In terms of their possible physiological effects, several experimental studies have shown that statins have anti-tumor properties on prostate cancer cells, such as on cell proliferation," Azoulay noted.
"The results of our study do corroborate these experimental studies," he added. "That being said, it is well-documented that long-term statin users are 'health-conscious' individuals. Thus, it is also possible that their healthy behavior may have contributed, at least in part, to the observed decreased risk with prostate cancer mortality."
But if further research upholds the current indications, would a statin regimen be advisable?
"Statins are generally safe drugs, though some rare adverse events can occur, such as muscle damage," Azoulay said. "This is especially relevant as certain prostate cancer treatments, such as androgen-deprivation therapy, may also affect muscle mass."
Future studies should assess whether statins can be used safely with other prostate cancer treatments, he added.
Dr. Anthony D'Amico, chief of radiation oncology at Brigham and Women's Hospital in Boston, suggested, however, the findings should be considered with caution.
"It is important to note that this is a study of association and not proof of cause and effect," he said, noting that only a large randomized trial can prove causation.
"Nevertheless, the study results are encouraging," he added, "and support a randomized trial to validate their findings for statin use in the pre- and post-(prostate cancer) diagnostic settings."
For more on prostate cancer, visit the U.S. National Institutes of Health (http://newsinhealth.nih.gov/issue/Oct2010/Feature2/ ).
SOURCES: Laurent Azoulay, Ph.D., Centre for Clinical Epidemiology, Lady Davis Institute, Jewish General Hospital, and department of oncology, McGill University, Montreal, Canada; Anthony D'Amico, M.D., Ph.D., chief, radiation oncology, Brigham and Women's Hospital, Boston; Nov. 4, 2013, Journal of Clinical Oncology, online