“Now we know that the location of the calcium in the arteries is particularly important in estimating a patient‘s potential risk,“ said the study‘s lead author Elizabeth Brown, Sc.D., research assistant professor in the Department of Biostatistics at the University of Washington in Seattle. The Multi-Ethnic Study of Atherosclerosis (MESA) began in July 2000.
The prospective study included 6,814 men and women between the ages of 45 and 84. The researchers compared CT image data for 3,252 participants with calcific plaque to data collected from 3,416 patients without calcific plaque. A calcium coverage score was developed to estimate the percentage of coronary arteries affected by plaque.
The patients were then followed up for a median period of 41 months to determine if there was a relationship between the distribution of calcium shown in the CT images and the likelihood heart attack or other cardiac event. The results showed that diabetes, hypertension and dyslipidemia (abnormal concentrations of lipids [fats] or lipoproteins in the blood) were highly associated with calcium coverage score.
The study also found that the calcium coverage score which takes into account the location of the calcium was a better predictor of future cardiac events than currently used measures that gauge only the amount of calcium present. On average, compared to patients without diabetes, patients with diabetes had 44 percent more of their coronary arteries affected by plaque. A twofold increase in calcium coverage score indicated a 34 percent increase in risk of heart attack or other serious cardiac event and a 52 percent increase in the risk of any cardiac event.
MEDICA.de; Source: Radiological Society of North America