Abstract 4999: High Remnant Lipoprotein Levels Are a Strong Predictor of Cardiovascular Events in Patients with Chronic Coronary Artery Disease and Metabolic Syndrome after Achieving LDL-Cholesterol Goals
NCEP ATPIII guidelines recommend non-HDL-cholesterol (C) as a secondary target of lipid-lowering therapy in patients with metabolic syndrome (MetS) after achieving LDL-C goals. Non-HDL-C contains remnant lipoprotein cholesterol which is a strong predictor of cardiovascular disease (CVD) events in MetS. This study examined the predictive value of remnant lipoprotein levels for CVD events in patients with coronary artery disease (CAD) and MetS after achieving LDL-C goals on lipid-lowering therapy. Serum levels of remnant lipoproteins (remnant-like lipoprotein particles cholesterol; RLP-C) were measured by an immunoseparation method in 302 consecutive patients with chronic CAD and MetS meeting ATP III criteria, and all patients had LDL-C levels < 100 mg/dL on lipid-lowering therapy that included statin (64%), fibrate (10%), and diet only (26%). All patients were prospectively followed-up for 48 months or until the occurrence of one of the following CVD events: cardiac death, non fatal myocardial infarction, unstable angina pectoris requiring revascularization, or ischemic stroke. During follow-up period, 43 CVD events occurred (cardiac death in 13 patients, non-fatal myocardial infarction in 3, unstable angina in 17, ischemic stroke in 10). In a multivariate Cox hazards analysis, higher levels of RLP-C (≥ 4.5 mg/dL, 50th percentile of the distribution), total apolipoprotein B (≥ 110 mg/dL, 75th percentile of the distribution), and non-HDL-C (≥ 130 mg/dL) and lower HDL-C levels (< 40 mg/dL in male, < 50 mg/dL in female) were significant predictors of CVD events (HR; 4.8, 2.3, 2.2, and 2.0, 95% CI 2.1 – 8.4, 1.2 – 4.7, 1.2 – 4.1, and 1.1 – 4.6, respectively, all p < 0.01) and were independent of body mass index, hypertension, diabetes, and triglyceride levels. The c-statistic showed that higher levels of RLP-C were the strongest predictor of CVD events, followed by total apolipoprotein B and non-HDL-C (area under ROC curve: 0.80, 0.77, and 0.76, respectively). RLP-C was a significant predictor of CVD events in patients with chronic CAD and MetS who had achieved LDL-C goals on lipid-lowering therapy. Remnant lipoprotein is an important target of lipid-lowering therapy in patients with CAD and MetS after achieving LDL-C goals.