Increased prevalence of significant coronary artery calcification in patients with diabetes

Coronary artery disease is the major cause of morbidity and mortality in patients with diabetes. Detection of coronary artery disease before the first myocardial infarction and before anginal symptoms will allow for strategies designed to reduce the cardiovascular event rate in this group of patients. Electron beam-computed tomography (EBCT) is a noninvasive technology for evaluating the extent of coronary artery atherosclerosis that relies on the detection of coronary artery calcium (CAC). We used EBCT to detect significant coronary artery atherosclerosis in diabetic patients without symptoms of heart disease.

We used EBCT to evaluate calcium in the coronary arteries of 139 consecutive diabetic patients scanned over a 20-month period. The CAC scores in this group were compared with a randomly selected nondiabetic control group and a control group that was selected to match a number of established cardiovascular risk factors.

Patients with diabetes had a significant increase in the prevalence of CAC scores > or =400 (25.9%) compared with the randomly selected (7.2%) and matched (14.4%) nondiabetic control groups. Scores in this range have been reported to be highly predictive for abnormal stress myocardial perfusion tomography and subsequent coronary events.

Our results, therefore, indicate a substantial prevalence of significant coronary artery disease in an asymptomatic diabetic patient population compared with nondiabetic control subjects. They also suggest that EBCT may be a useful approach for selecting a group of diabetic subjects who would benefit most from additional evaluation for subclinical coronary artery disease.