Lp-PLA2 (PLAC): Relationship to Conventional Risk Factors and Cardioprotective Drug Therapies in Coronary Patients

Abstract

PLAC is a blood test measuring lipoprotein-associated phospholipase A2 (Lp-PLA2), a marker of arterial inflammation. Elevated levels of PLAC (> 235 ng/mL) suggest an increased risk of cardiovascular events, whereas reduced values (especially < 160 ng/mL) are associated with a low annual mortality. PURPOSE: To determine the associations among PLAC values and other indices of health among cardiac patients participating in a formalized risk reduction program. METHODS: Patients enrolled in Phase III cardiac rehabilitation (n = 86; 69 men, 17 women) received 6 months of education and counseling focused on exercise progression, nutrition, stress management, and risk factor awareness. Patients also updated blood chemistry studies, including a lipid/lipoprotein profile, fasting blood glucose (FBG), glycosylated hemoglobin (HgA1C), and PLAC. RESULTS: Patients taking a statin had significantly lower mean PLAC values than those not on statins (p = 0.038), 163 ± 47 vs 194 ± 56 ng/mL, respectively. Positive correlations were observed for LDL and PLAC (r = 0.28, p = 0.011) and total cholesterol (TC) and PLAC (r = 0.26, p = 0.018). PLAC values were unrelated to gender, diabetic status, or aspirin therapy; however, PLAC and BMI were inversely related (r = -0.22, p = 0.047). When patients with and without ideal PLAC levels were compared, the former had significantly lower LDL values and a higher frequency of statin usage. Mean ± SD for selected variables are shown:TABLECONCLUSION: In this group of cardiac patients, statin usage was associated with lower LDL and TC values, as well as decreased arterial inflammation measured by PLAC testing. These data suggest that the cardioprotective effect