Impact of Diabetes Mellitus on the Treatment Effect of Percutaneous or Surgical Revascularization for Patients With Unprotected Left Main Coronary Artery Disease. A Subgroup Analysis of the MAIN-COMPARE Study

Objectives: This study sought to investigate whether the outcome of drug-eluting stent (DES) treatment and that of coronary artery bypass grafting (CABG) differed in diabetic and nondiabetic patients with unprotected left main coronary artery (LMCA) disease. Background: Diabetes mellitus has been shown to be a risk factor for adverse events and a major determinant in selection of a revascularization strategy in patients with multivessel or LMCA disease. Methods: A total of 1,474 patients with unprotected LMCA stenosis who received DES (n = 784) or underwent CABG (n = 690) were examined. We compared the effects of these 2 treatments on long-term clinical outcomes (death; the composite of death, Q-wave myocardial infarction [MI], or stroke; and target vessel revascularization [TVR]), according to diabetic status. Results: After adjustment of covariates, the risk of death (hazard ratio [HR]: 0.95, 95% confidence interval [CI]: 0.62 to 1.46, p = 0.83) and the composite of death, Q-wave MI, or stroke (HR: 0.96, 95% CI: 0.65 to 1.42, p = 0.85) at 3 years were similar in the DES and CABG groups. However, the rate of TVR was significantly higher in the DES group (HR: 4.31, 95% CI: 2.28 to 8.15, p < 0.001). These trends were consistent in both diabetic and nondiabetic patients. We also did not observe a diabetes-associated excess risk of death (p_interaction = 0.90 and 0.16), or a composite of death, Q-wave MI, or stroke (p_interaction = 0.68 and 0.93), or TVR (p_interaction = 0.23 and 0.92), between patients receiving either treatment. Conclusions: The prognostic impact of diabetes on long-term treatment with DES or CABG for patients with unprotected LMCA disease was minimal.