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.