Researchers Find Possibility of Heart Disease Causing Prostate Cancer
Duke researchers find evidence linking prostate cancer and coronary artery disease
Feb. 8, 2012 – Is heart disease the cause of prostate cancer? New research from the Duke Cancer Institute
has found a “significant correlation” between coronary artery disease and prostate cancer, suggesting they may have shared causes.
If confirmed that heart disease is a risk factor for prostate cancer, the malignancy might be combated in
part by lifestyle changes such as weight loss, exercise and a healthy diet, which are known to prevent heart disease.
"What's good for the heart may be good for the prostate," said Jean-Alfred Thomas II, MD, a post-doctoral
fellow in the Division of Urology at Duke and lead author of the study, which appears
online this month in the journal Cancer Epidemiology, Biomarkers & Prevention.
Cancer Statistics 2011 shows among men the
reduction in lung, prostate, and colorectal cancers is nearly 80% of
decline; among women, almost 60% of decrease in breast and colorectal -
see chances of seniors getting cancer
Coronary artery disease - narrowing of the small blood vessels that supply blood and oxygen to the
heart - kills more adults in the United States than any other cause, accounting for one
in four deaths. Risk factors include inactivity, obesity, high blood pressure and cholesterol, cigarette smoking, and diabetes.
Similarly, prostate cancer is a common killer. It's the second-most lethal cancer for U.S. men, behind
lung cancer, with about 240,000 new cases diagnosed a year, and 34,000 deaths.
Previous studies exploring the relationship between coronary artery disease and prostate cancer risk have
found conflicting results, making it difficult to determine whether the malignancy is fueled by poor lifestyle choices.
In the current study, the Duke team used data from 6,390 men enrolled in a large study called REDUCE, a
four-year, randomized trial to test the prostate cancer risk reduction benefits of a drug called dutasteride.
All the study participants had a prostate biopsy at the two- and four-year marks, regardless of their PSA
levels. They also provided a detailed medical history that included their weight, incidence of heart disease, alcohol intake, medication use,
and other factors.
Among the men in the study, 547 reported a pre-enrollment history of coronary artery disease. This group
of men tended to be older, heavier and less healthy, with higher baseline PSA levels, plus more diabetes, hypertension, and high cholesterol.
The men were also much more likely to develop prostate cancer, even after accounting for all the baseline differences.
Having coronary artery disease increased the men's risk of prostate cancer by 35 percent, with the risk
rising over time. The group was 24 percent more likely to be diagnosed with prostate cancer within the first two years of the study than men
who reported no heart disease, and by four years into the study, this group's prostate cancer risk was 74 percent higher.
"We controlled for a number of risk factors, including hypertension, taking statins, or aspirin," Thomas
said. "We don't have a good grasp on what's causing the link, but we are observing this association."
Stephen Freedland, MD, associate professor of surgery and pathology in the Division of Urology at Duke
and senior author of the paper, said the study had some shortcomings. Notably, it relied on data from a previous trial that didn't account for
factors such as diet, physical activity and severity of heart disease that may have influenced the results.
But Freedland said the study eliminated a screening bias common in previous findings that correlated
prostate cancer and heart disease using men with high PSA levels.
"This is giving us a lot of good ideas for what to look at next," Freedland said, noting that the overlap
between prostate cancer and other diseases associated with poor health habits is a focus of his research group.
In addition to Thomas and Freedland, study authors from Duke include Leah Gerber; Lionel L. Bañez; and
Daniel M. Moreira. The Duke authors also hold positions in the surgery section of the Durham VA Medical Center. Study author Roger S.
Rittmaster is from GlaxoSmithKline; Gerald L. Andriole is from Washington University School of Medicine in St. Louis.
Freedland and Andriole are paid consultants to GSK and have research support from the company.
The study was supported by GSK; the Department of Veterans Affairs; Duke University Department of Surgery
and Division of Urology; Department of Defense Prostate Cancer Research Program; and the American Urological Association Foundation/Astellas
Rising Star in Urology Award.