A new study from suggests that statins either alone or in combination with metformin may reduce the risk of dying from prostate cancer. The study’s findings were presented at the American Society of Clinical Oncology annual meeting in Chicago. The study was carried out by Grace L. Lu-Yao, PhD, an epidemiologist at the Rutgers Cancer Institute of New Jersey in New Brunswick.

The study analyzed a total of 22,110 people who were all considered high-risk prostate cancer patients. Among the 22,110 high-risk prostate cancer patients, 1,365 of them died from prostate cancer. And among these 1,365 high-risk prostate cancer patients who died, Lu-Yao and her colleagues found that the reduction in the risk of prostate cancer-specific mortality was most prominent among patients who had metabolic syndrome or were obese.

According to Dr. Lu-Yao, “A recent preclinical study showed that combined statin and metformin should have a synergistic effect to reduce metastasis [in patients with prostate cancer], and should be more effective than the standard chemotherapy regimen available.” She also said, “We conducted this study because there really is no clinical data out there.”

According to the study’s background investigation conducted by the researchers, mortality risk is increased significantly among prostate cancer patients who are either obese or have metabolic syndrome. The researchers said that ‘pre-clinical studies have suggested that the combination of statins and metformin inhibited metastasis with greater efficacy than standard docetaxel chemotherapy with less toxicity.’ 

The researchers analyzed and evaluated SEER–Medicare linked data to identify patients with high-risk prostate cancer between 2007 and 2009. All the patients in the study were identified as having stage III or stage IV prostate cancer, a PSA level greater than 20, or a Gleason score between 8 and 10. The researchers also evaluated Medicare Part D Event files to determine if and which prescription drugs were being used by the patients. They then used the ICD-9 diagnosis codes 278, 278.01 or 277.7 to identify obesity and metabolic syndromes among the patients in the study.

The analysis included a total of 22,110 men with high-risk prostate cancer. 1,365 of the 22,110 men with high-risk prostate cancer had died by the end of the study. The researchers found that overall, 1,356 men used statins and metformin, 4,481 men used statins alone and 471 men used metformin alone.

The researchers concluded that the data showed that the use of combination statin and metformin therapy resulted in a 43 percent decrease in disease-specific mortality, compared to not using combination statin and metformin therapy. They also found that combination statin and metformin therapy also improved prostate cancer-specific mortality among men with obesity and metabolic syndrome. Among patients who were obese or had metabolic syndrome, combination statin and metformin therapy was associated with a 70 percent decreased risk of prostate cancer-specific mortality.

The researchers also found that using statins alone also showed a significant improvement in the overall population as well as among men with obesity and metabolic syndrome. Statin treatment alone was associated with a 40 percent decreased risk of prostate cancer-specific mortality, compared to those who didn’t use the medication. And among patients who were obese or had metabolic syndrome, statin treatment alone was associated with a 91 percent decreased risk of prostate cancer-specific mortality.

Among patients who were not obese or did not have metabolic syndrome, combination statin and metformin therapy was associated with a 40 percent decreased risk and statins alone was associated with a 36 percent decreased risk of prostate cancer-specific mortality.

More research is needed to confirm their findings.

“Our findings show a lot of promise. We can reduce prostate cancer mortality by using this relatively safe, nontoxic drug. We need to learn more about who are likely to be the target population to benefit from this combination, along with the potency, timing and duration [of treatment]. Then we can launch a clinical trial to get the definitive answer,” said Dr. Lu-Yao.

What is metabolic syndrome? Metabolic syndrome is a group of risk factors that raises your risk for heart disease, diabetes, and stroke. Compared to people without metabolic syndrome, people with are, twice as likely to develop heart disease, five times as likely to develop Type 2 diabetes, three times as likely to have heart attack or stroke, and twice as likely to die overall. Previous studies have shown that the Mediterranean can help reduce metabolic syndrome.

The link between obesity and cancer risk is not completely understood. However, we do know that excess weight may increase cancer risk by affecting immune system function and inflammation, levels of certain hormones (i.e. insulin and estrogen), factors that regulate cell division, or proteins that influence how the body uses certain hormones. With prostate cancer specifically, when visceral fat - fat inside the body - surrounds the prostate, it can secrete hormones that feed tumor cells and increase prostate cancer growth.

Currently, about 71 percent of men in the United States are overweight or obese. For adults, overweight and obesity ranges are calculated using height and weight to get body mass index (BMI), which correlates with the amount of body fat a person has. An adult with a BMI of 25.0 to 29.9 is considered overweight, while an adult with a BMI of 30 or higher is considered obese.

It is estimated that advanced prostate cancer cases in the U.S. could be prevented by maintaining a healthy weight. While factors like age, race, and family history are out of our control, living a healthy lifestyle is in our control. The best way to reduce your risk for prostate cancer include maintain a healthy weight, eat a healthy diet, and be physically active.