Update in Endocrinology

Diabetes Mellitus

Myocardial Perfusion Imaging Should Be Considered To Detect Silent Coronary Artery Disease in Diabetic Patients

American Diabetes Association (ADA) guidelines (1) recommend routine exercise electrocardiogram (ECG) stress testing to detect silent coronary artery disease in diabetic patients when 2 or more additional risk factors are present. The Detection of Ischemia in Asymptomatic Diabetics (DIAD) study tested the effectiveness of these guidelines. Patients with type 2 diabetes ranging in age from 50 to 75 years (n = 1123) with no known coronary artery disease were randomly assigned to 2 groups: One group (n = 522) underwent standard exercise ECG stress testing followed by ECG-gated regional myocardial perfusion imaging by single-photon emission computed tomography (SPECT) at rest and after exercise, whereas the second group (n = 522) did not undergo testing. Both groups were reevaluated 5 years later.

The results indicated that 22% of the patients who underwent testing (n = 113) were found to have evidence of silent coronary disease on the basis of moderate to large perfusion defects (n = 33), ventricular dilatation, ventricular dysfunction at rest, or adenosine-induced ST-segment depression. The strongest predictors for coronary disease were male sex (odds ratio, 2.5 [P < 0.03]), duration of diabetes (odds ratio, 5.2 [P < 0.002]), and abnormal response to the Valsalva maneuver (odds ratio, 5.6 [P < 0.001]). The researchers reported that 60% of the patient sample (n = 306) had 2 or more risk factors, which made them eligible for screening by ADA guidelines, whereas 204 patients had fewer than 2 risk factors. Of these 204 patients, 45 …