Heart Disease, Colon Cancer Link?
People With Coronary Artery Disease May Be More Likely to Have Colon Cancer
Sept. 25, 2007 -- What's bad for your heart may also make you more likely to develop colorectal cancer, a Hong Kong study shows.
The coronary arteries supply blood to heart muscle. Coronary artery disease can lead to a heart attack. Heart disease is the leading cause of death for U.S. adults.
Heart disease and colorectal cancer share some common risk factors.
For instance, smoking and diabetes make both diseases more likely, note the University of Hong Kong's Annie On On Chan, MD, and colleagues.
They report that colorectal cancer (cancer of the colon or rectum) may be more common among people with heart disease than other people.
The findings appear in The Journal of the American Medical Association.
Heart Disease and Colon Cancer
Chan's study included 706 adults living in Hong Kong who were in their early 60s, on average.
The group included 206 heart disease patients, 208 people without heart disease, and 207 people who weren't screened for heart disease.
Each participant had a colonoscopy, in which doctors screen the colon and rectum for cancers and other abnormal growths.
None was taking aspirin or cholesterol-lowering statin drugs, which may help prevent colon cancer. None had undergone colorectal surgery or had a colonoscopy in the past decade.
The doctors found colorectal cancer in about 4% of the heart disease patients, less than 1% of those without heart disease, and 1.4% of those not screened for heart disease.
Suspicious polyps were also more common in the heart disease patients than in the other participants, the study shows.
Smokers and people with metabolic syndrome were at greater risk for heart disease and colorectal cancer.
Metabolic syndrome is a cluster of abnormalities including:
Metabolic syndrome makes heart disease and type 2 diabetes more likely.
Chan's study doesn't show how heart disease affects colorectal cancer risk. But inflammation and poor response to insulin (a hormone that controls blood sugar) may be involved, Chan's team suggests.
The researchers considered many colorectal cancer risk factors, including family history of colorectal cancer. But they didn't have data on every possible influence that might have influenced the odds of developing colorectal cancer.