Calcium in Arteries Ups Heart Attack Risk

Even when cholesterol is being controlled, increasing deposits of calcium in coronary arteries may increase the odds of having a heart attack.

Even when cholesterol is being controlled, increasing deposits of calcium in coronary arteries may increase the odds of having a heart attack. In a study of patients on cholesterol-lowering “statin” treatment, those who had a heart attack during 3 years of follow up had significantly more buildup of coronary artery calcium than those who did not have a heart attack, despite similar LDL (“bad”) cholesterol levels. “Continued expansion of coronary artery calcium may indicate failure of some patients to benefit from statin therapy and an increased risk of having cardiovascular events,” researchers suggest in the July issue of Arteriosclerosis, Thrombosis, and Vascular Biology. In comments to Reuters Health, Dr. Paolo Raggi from Tulane University in New Orleans, Louisiana, who led the study, said statins are “greatly effective at reducing the rate of heart attacks, but the event rate is reduced at best by 35 percent. Why are so many people–65 percent of those treated–still having events?” In the current study, Raggi and his colleagues monitored calcium buildup in patients taking statins. Of 495 participants with similar LDL levels and no symptoms, 41 had a heart attack during follow up. On average, these patients showed a “greater and faster” accumulation of coronary artery calcium than those who did not, Raggi said. In particular, he noted, the risk of a heart attack “was about 17-fold greater” when calcium progression was substantial — more than 15 percent per year — than when calcium buildup was absent. However, the best predictor of a heart attack “was a combination of LDL level and calcium change,” Raggi explained. This suggests, he concluded, that in addition to monitoring LDL cholesterol, doctors should also “include some measurement of vascular health in our assessment of the individual patient to have a clearer idea of his or her health status.” (SOURCE: Arteriosclerosis, Thrombosis, and Vascular Biology: Reuters Health News: July 2004.)