Coronary Artery Calcium Detected by Tomography May Predict Heart Disease

NEW YORK (Reuters Health) – The presence of electron beam computed tomography (EBCT) coronary artery calcium (CAC) may be predictive of the development of coronary artery disease, according to an early release report to be published in the May 27th issue of Circulation.

“Conventional coronary artery disease (CAD) risk factors fail to explain nearly 50% of CAD events,” Dr. George T. Kondos, of University of Illinois as Chicago College of Medicine, and colleagues note. They examined the association between EBCT CAC and cardiac events in 8855 initially asymptomatic low- to intermediate-risk patients. The team adjusted for hypercholesterolemia, hypertension, diabetes, and a history of smoking.

The subjects completed questionnaires on conventional CAD risk factors. The investigators used medical records and death certificates to determine the occurrence of cardiac events over a follow-up of 37 months. They report that CAC was detected in 74% and 51% of men and women, respectively. Ninety-five percent of those with any event exhibited measurable CAC, compared with 67% of those without events.

Among men, 192 events were reported. These were significantly associated with the presence of CAC (relative risk ÄRRÅ = 10.5, p < 0.001), diabetes (RR = 1.98, p = 0.008), and smoking (RR = 1.4, p = 0.025). Thirty-two events were observed in women. These were associated with the presence of CAC (RR = 2.6, p = 0.037), but not risk factors. “Although office-based risk assessment remains the current recommendation for risk stratification in the general population, the association between EBCT CAC and cardiac events observed in this study…provides incremental information beyond that defined by single or combined conventional CAD risk factor assessment,” Dr. Kondos and colleagues explain. Circulation 2003;107:http://www.circulationaha.org