A study in the Journal of the American College of Cardiology suggests that a coronary calcium scan can help people at intermediate risk of coronary artery disease (CAD) decide whether to start statin therapy. A coronary calcium scan is an imaging technique-also called electron-beam computed tomography or a CT scan-that detects calcium deposits in coronary arteries, which may signal the presence of CAD.
Researchers looked at data on more than 4,500 ethnically diverse men and women, ages 45 to 84, recruited over a decade ago for a large study on cardiovascular risk. All of the subjects had scans. Using the current cholesterol guidelines, statins would be recommended or considered for 50 percent of them-most of whom were at intermediate or borderline risk.
Yet 44 percent of these statin-eligible subjects had a calcium score of zero, indicating a very low risk for CAD. During a 10-year follow-up, the actual incidence of heart attacks and other coronary events in this group was half or less than what the risk calculator in the guidelines predicted. Many of these people, say the researchers, could reasonably opt not to take a statin if that was their preference.
The results of this study bolster earlier research on the potential value of coronary calcium screening in primary prevention. However, we dont think screening should be done routinely for everyone at intermediate risk. The study was observational, so it did not prove that outcomes would be better with CT testing. Also, scans can turn up other abnormalities, leading to further tests that, in many cases, prove unnecessary. Test costs and radiation exposure are also concerns. Still, for anyone at intermediate risk, it is worthwhile discussing coronary calcium screening with your doctor, especially if you have concerns about taking a statin.