Coronary artery calcium score may predict odds of dying

Harvard Heart Letter

A noninvasive test called a coronary artery calcium (CAC) scan, which measures specks of calcium in the heart's arteries, can help predict a person's risk of heart disease. New research suggests that a CAC score (which ranges from 0 to 1,000 or more) also can accurately predict a person's risk of dying over the following decade and a half.

The study included 9,715 people who were referred to a cardiology clinic and underwent CAC scans. All had risk factors for heart disease (such as high blood pressure, diabetes, or a family history) but no symptoms. During the nearly 15-year follow-up, people with scores of 400 or greater had a 20% risk of dying of any cause. By comparison, the risk of death was only 3% for people with no signs of calcium in their arteries (a CAC score of 0).

The study appears in the July 7, 2015, Annals of Internal Medicine.

Despite the possible benefits of a CAC scan—which include more aggressive treatments to lower heart disease risk for people with high scores—the tests are not risk-free. There's theoretically a very small cancer risk caused by radiation exposure from the test, estimated to potentially affect 12 of every 10,000 people screened.