Impact of metabolic syndrome and diabetes on prognosis and outcomes with early percutaneous coronary intervention in the COURAGE (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation) trial

Abstract

Objectives: Our purpose was to clarify the clinical utility of identifying metabolic syndrome (MetS) in patients with coronary artery disease (CAD).

Background: It is uncertain whether MetS influences prognosis in patients with CAD and whether the risk associated with MetS exceeds the risk associated with the sum of its individual components.

Methods: In a post hoc analysis, we compared the incidence of death or myocardial infarction (MI) in stable CAD patients in the COURAGE (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation) trial according to the presence (+) or absence (-) of MetS and diabetes: Group A, -MetS/-diabetes; Group B, +MetS/-diabetes; Group C, -MetS/+diabetes; and Group D, +MetS/+diabetes. We explored which MetS components best predicted adverse outcomes and whether MetS had independent prognostic significance beyond its individual components.

Results: Of 2,248 patients, 61% had MetS and 34% diabetes. Risk for death or MI increased from Group A (14%) to Group D (25%, p < 0.001). Hypertension (hazard ratio [HR]: 1.30; 95% confidence interval [CI]: 0.98 to 1.71; p = 0.07), low high-density lipoprotein cholesterol (HR: 1.26; 95% CI: 1.03 to 1.55; p = 0.03), and elevated glucose (HR: 1.17; 95% CI: 0.96 to 1.47; p = 0.11) most strongly predicted death or MI. MetS was associated with an increased risk of death or MI (unadjusted HR: 1.41; 95% CI: 1.15 to 1.73; p = 0.001). However, after adjusting for its individual components, MetS was no longer significantly associated with outcome (HR: 1.15; 95% CI: 0.79 to 1.68; p = 0.46). Allocation to initial percutaneous coronary intervention did not affect the incidence of death or MI within any group.

Conclusions: Among stable CAD patients in the COURAGE trial, the presence of MetS identified increased risk for death or MI, but MetS did not have independent prognostic significance after adjusting for its constituent components. The addition of early percutaneous coronary intervention to optimal medical therapy did not significantly reduce the risk of death or MI regardless of MetS or diabetes status. (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation [COURAGE]; NCT00007657).