Lipoprotein-Associated Phospholipase A2 Bound on High-Density Lipoprotein Is Associated With Lower Risk for Cardiac Death in Stable Coronary Artery Disease Patients

Objectives The aim of this study was to examine the prognostic value of lipoprotein-associated phospholipase A2 (Lp-PLA2 ) associated with high-density lipoprotein (HDL) (HDL-Lp-PLA2 ) in patients with stable coronary artery disease (CAD). Background Lp-PLA2 is a novel risk factor for cardiovascular disease. It has been postulated that the role of Lp-PLA2 in atherosclerosis may depend on the type of lipoprotein with which it is associated. Methods Total plasma Lp-PLA2 and HDL-Lp-PLA2 mass and activity, lipids, and C-reactive protein were measured in 524 consecutive patients with stable CAD who were followed for a median of 34 months. The primary endpoint was cardiac death, and the secondary endpoint was hospitalization for acute coronary syndromes, myocardial revascularization, arrhythmic event, or stroke. Results Follow-up data were obtained from 477 patients. One hundred twenty-three patients (25.8%) presented with cardiovascular events (24 cardiac deaths, 47 acute coronary syndromes, 28 revascularizations, 22 arrhythmic events, and 2 strokes). Total plasma Lp-PLA2 mass and activity were predictors of cardiac death (hazard ratio [HR]: 1.013; 95% confidence interval [CI]: 1.005 to 1.021; p = 0.002; and HR: 1.040; 95% CI: 1.005 to 1.076; p = 0.025, respectively) after adjustment for traditional risk factors for CAD. In contrast, HDL-Lp-PLA2 mass and activity were associated with lower risk for cardiac death (HR: 0.972; 95% CI: 0.952 to 0.993; p = 0.010; and HR: 0.689; 95% CI: 0.496 to 0.957; p = 0.026, respectively) after adjustment for traditional risk factors for CAD. Conclusions Total plasma Lp-PLA2 is a predictor of cardiac death, while HDL-Lp-PLA2 is associated with lower risk for cardiac death in patients with stable CAD, independently of other traditional cardiovascular risk factors.