Coronary Calcium Score Shows Usefulness in Two Studies
Coronary artery calcium better predictor than carotid thickness; effective for pointing out risk in elderly
TUESDAY, June 24 (HealthDay News) -- Coronary artery calcium (CAC) score was a better predictor for coronary heart disease and total cardiovascular disease than carotid intima-media thickness in middle-aged and older adults, and CAC scoring is effective for stratifying risk even in the elderly, according to studies in the June 23 Archives of Internal Medicine and the July 1 Journal of the American College of Cardiology.
In the first study, Aaron R. Folsom, M.D., of the University of Minnesota in Minneapolis, and colleagues analyzed data from 6,698 subjects aged 45 to 84 who were free of cardiovascular disease. The researchers measured their CAC and carotid intima-media thickness (IMT) at baseline and followed the cohort for a median 5.3 years. The hazard ratios for cardiovascular disease and coronary heart disease increased by greater amounts for rising CAC scores compared with IMT scores.
In the second study, Paolo Raggi, M.D., of Emory University School of Medicine in Atlanta, and colleagues assessed data from 35,388 patients who underwent CAC screening with electron beam tomography, dividing the group into six age deciles for analysis. Higher scores were associated with lower survival across all age deciles.
"Intima-media thickness was a modestly better predictor of stroke than CAC score, although there were few stroke events," Folsom and colleagues write. "The modestly better prediction of stroke by IMT and clearly better prediction of coronary heart disease by CAC score likely reflects their different vascular territories. The potential choice between measuring CAC or IMT or neither in preventive cardiology depends on other considerations as well (e.g., differences in radiation exposure, cost and availability). The CAC score may be most relevant in the United States, where coronary heart disease is common. If risk of stroke in families with histories of early stroke were a concern, then carotid IMT may be very relevant."
In the Folsom study, a co-author disclosed financial relationships with a variety of pharmaceutical companies, and in the Raggi study, a co-author disclosed financial relationships with several companies. A co-author on both studies reported a relationship with General Electric.