Abstract 846: Intensive Lipid-lowering Therapy May Reduce the Increased Cardiovascular Risk Associated With Elevated Lp-PLA2 Levels
Background: Lipoprotein-associated phospholipase A2 (Lp-PLA2), an enzyme present in the circulation and in atherosclerotic plaque, is an inflammatory marker with potential for use as a predictor of cardiovascular risk. In the Treating to New Targets (TNT) study, intensive lipid-lowering therapy with atorvastatin (ATV) 80 mg was demonstrated to provide significant clinical benefit compared with ATV 10 mg over 4.9 years of follow-up in patients with stable coronary heart disease (CHD). The current post-hoc, nested, case-control substudy was designed to investigate the value of Lp-PLA2 levels in the prediction of major cardiovascular events (MCVE) (defined as cardiac death, MI, stroke, resuscitated cardiac arrest).
Methods: Baseline Lp-PLA2 was measured after an 8-week ATV 10 mg run-in period. Analyses were conducted on blood samples taken from 506 of the 982 patients who experienced a MCVE, and 1012 control patients without events. Baseline characteristics of the substudy and total TNT populations were similar.
Results: Median baseline levels of Lp-PLA2 were similar in the two treatment groups (323.0 ng/mL in the ATV 80 mg group; 325.5 ng/mL in the ATV 10 mg group). Higher Lp-PLA2 values were associated with an increase in risk of MCVE in the ATV 10 mg group, and a lower risk of MCVE in the ATV 80 mg group (Table⇓). These observations remained consistent following adjustment for age and gender. The interaction between treatment group and baseline Lp-PLA2 level was significant (P=0.039).
Conclusion: Higher Lp-PLA2 levels were predictive of increased risk of MCVE among patients receiving ATV 10 mg but not among those receiving ATV 80 mg. Our data suggest that in stable CHD patients, intensive lipid-lowering treatment may diminish the cardiovascular risk associated with elevated Lp-PLA2 levels.