Relationship of Oxidized Phospholipids on Apolipoprotein B-100 to Cardiovascular Outcomes in Patients Treated With Intensive Versus Moderate Atorvastatin Therapy: The TNT Trial

Abstract

BackgroundOxidized phospholipids on apolipoprotein B-100 (OxPL-apoB) is a biomarker of increased risk for major adverse cardiovascular events (MACE) in community cohorts, but its role in patients with stable coronary heart disease (CHD) is unknown. ObjectivesThis study sought to examine the relationship between these oxidative biomarkers and cardiovascular outcomes in patients with established CHD. MethodsIn a random sample from the TNT (Treating to New Targets) trial, OxPL-apoB levels were measured in 1,503 patients at randomization (after an 8-week run-in period taking atorvastatin 10 mg) and 1 year after being randomized to atorvastatin 10 or 80 mg. We examined the association between baseline levels of OxPL-apoB and MACE, defined as death from CHD, nonfatal myocardial infarction, resuscitation after cardiac arrest, and fatal/nonfatal stroke, as well as the effect of statin therapy on OxPL-apoB levels and MACE. ResultsPatients with events (n = 156) had higher randomization levels of OxPL-apoB than those without events (p = 0.025). For the overall cohort, randomization levels of OxPL-apoB predicted subsequent MACE (hazard ratio [HR]: 1.21; 95% confidence interval: 1.04 to 1.41; p = 0.018) per doubling and tertile 3 versus tertile 1 (hazard ratio: 1.69; 95% confidence interval [CI]: 1.14 to 2.49; p = 0.01) after multivariate adjustment for age, sex, body mass index, among others, and treatment assignment. In the atorvastatin 10-mg group, tertile 3 was associated with a higher risk of MACE compared to the first tertile (HR: 2.08; 95% CI: 1.20 to 3.61; p = 0.01) but this was not significant in the atorvastatin 80-mg group (HR: 1.40; 95% CI: 0.80 to 2.46; p = 0.24). ConclusionsElevated OxPL-apoB levels predict secondary MACE in patients with stable CHD, a risk that is mitigated by atorvastatin 80 mg. (A Study to Determine the Degree of Additional Reduction in CV Risk in Lowering LDL Below Minimum Target Levels [TNT]; NCT00327691)