Higher Rates of Colorectal Cancer in Patients with Coronary Artery

Higher Rates of Colorectal Cancer in Patients with Coronary Artery Disease

According to the results of a study conducted in Hong Kong, patients with coronary artery disease have a higher rate of colorectal polyps and colorectal cancer than individuals without coronary artery disease. These results were published in the Journal of the American Medical Association.

Colorectal cancer is the second leading cause of cancer-related deaths in the U.S. The disease develops in the large intestine, which includes the colon (the longest part of the large intestine) and the rectum (the last several inches).

Coronary artery disease refers to the hardening and narrowing of arteries that supply blood to the heart. It is the leading cause of death among both men and women in the United States.

Factors that may increase the risk of both colorectal cancer and coronary artery disease include obesity, physical inactivity, diabetes, and smoking. These and other shared risk factors may explain previously reported links between the two conditions.

To further evaluate the link between coronary artery disease and colorectal cancer, researchers in Hong Kong conducted a study among three groups of people: 1) patients who had a coronary angiogram and were found to have coronary artery disease; 2) patients who had a coronary angiogram and were found not to have coronary artery disease; and 3) a sample of individuals from the general population.

The study excluded patients who had taken aspirin or a statin for more than one year, as well as patients who had a history of colorectal polyps, colorectal cancer, or other colon problems.

All patients in the study received a colonoscopy.

Colorectal growths (polyps or cancer) were detected in 34% of patients with coronary artery disease, 18.8% of patients without coronary artery disease, and 20.8% of individuals in the general population sample.
Colorectal cancer was detected in 4.4% of patients with coronary artery disease, 0.5% of patients without coronary artery disease, and 1.4% of individuals in the general population sample.
The link between coronary artery disease and colorectal cancer was particularly strong for smokers and individuals with the metabolic syndrome. The metabolic syndrome involves a combination of conditions such as abdominal obesity, insulin resistance, high blood pressure, and abnormal cholesterol and triglyceride levels.
This study supports previous reports that colorectal cancer is more common in patients with coronary artery disease than in the general population. Smokers and patients with the metabolic syndrome have an increased risk of developing both conditions.

Reference: Chan AOO, Jim MH, Lam KF et al. Prevalence of colorectal neoplasm among patients with newly diagnosed coronary artery disease. JAMA. 2007;298:1412-1419.