Cardiac outcomes after screening for asymptomatic coronary artery disease in patients with type 2 diabetes: the DIAD study: a randomized controlled trial.

Description

Because coronary artery disease (CAD) is the major cause of mortality and morbidity in patients with type 2 diabetes, this study assessed whether routine screening for CAD could identify patients with type 2 diabetes at high cardiac risk and whether it had an impact on cardiac outcomes. In the Detection of Ischemia in Asymptomatic Diabetics (DIAD) study, 1,123 patients with type 2 diabetes but no symptoms of CAD were randomly assigned to be screened with adenosine-stress radionuclide myocardial perfusion imaging (MPI) vs. no screening. The cumulative cardiac event rate over the 4.8 years of follow-up was 2.9%. There were 15 events in the screening group vs. 17 events in the no-screening group (hazard ratio: 0.88, 95% CI: 0.44-1.88, p=0.73). Among the screened patients, 409 (78%) had normal test results and 50 (10%) had small MPI defects. Only 2% of the 409 participants with normal MPI results and 2% of the 50 subjects with small MPI defects had hard cardiac events compared to 12.1% of 33 patients with moderate or large MPI defects (hazard ratio: 6.3, 95% CI: 1.9-20.1, p=0.001). The rate of coronary revascularization was low in both groups (hazard ratio: 0.71, 95% CI: 0.45-1.1, p=0.14). In this study, the cardiac event rate was low in type 2 diabetic patients and was not significantly altered by MPI screening.