Comparison of Cardiac Events and Survival Between Asymptomatic Diabetic and Nondiabetic Patients: Coronary CT Study.

Background: Although coronary computed tomography angiography (CCTA) is useful for risk stratification in patients with diabetes, limited data is available regarding its prognostic value in asymptomatic patients with type 2 diabetes mellitus (T2DMs). Therefore, we aimed to evaluate the utility of CCTA in coronary artery disease (CAD) risk stratification in T2DMs compared to that in patients without diabetes mellitus (non-DMs).

Methods: We selected 565 T2DMs and 1,130 non-DMs using propensity score matching from the Evaluation of Subclinical Coronary atherosclerosis for Risk Stratification Using the Coronary Computed Tomography Angiography (ESCORT) study of 5,142 asymptomatic individuals. We evaluated CCTA findings and confirmed the occurrence of major adverse cardiac events (MACE; cardiac death, non-fatal myocardial infarction, and unstable angina) and total cardiac events (TCE; MACE plus coronary revascularization) during follow-up using Cox proportional hazards analysis and Kaplan-Meier survival curves.

Results: Over a median follow-up of 47 months, MACE and TCE occurred significantly more in T2DMs than in non-DMs (4.2% vs. 1.7% and 7.8% vs. 4.3%, respectively, all P < 0.001). The Cox regression model identified T2DMs, obstructive stenosis, and proximally located plaques as independent predictors of MACE and TCE (all P < 0.05). Kaplan-Meier curve analysis revealed that survival rate was dependent on stenosis grade (log-rank P < 0.001) and differed significantly in the presence of T2DMs among patients with obstructive stenosis (P < 0.05).

Conclusion: While diabetes is an independent risk factor for CAD, its impact on survival rate varies with the severity of CAD, highlighting the value of CCTA as a prognostic tool for CAD risk stratification in asymptomatic T2DMs.

Trial registration: ClinicalTrials.gov Identifier: NCT01416532.