Abstract 3601: Remnant Lipoprotein is Superior to Non-HDL-cholesterol for Prediction of Cardiovascular Events in Patients with Coronary Artery Disease after Achievement of LDL-cholesterol Goals
NCEP ATPIII guidelines recommend non-HDL-cholesterol (C) as a secondary target for management of hyperlipidemia after achieving LDL-C goals. Non-HDL-C contains remnant lipoprotein cholesterol which is known to be a strong predictor of cardiovascular diseases (CVD) events. This study examined predictive value of remnant lipoprotein for CVD in patients with coronary artery disease (CAD) after achieving LDL-C goals on lipid-lowering therapy.
Methods and Results: Fasting serum levels of remnant lipoproteins (remnant-like lipoprotein particles cholesterol; RLP-C) were measured by an immunoseparation method in 536 consecutive patients with CAD who had LDL-C levels < 100 mg/dL on lipid-lowering treatment, including statin (61%), fibrate (12%), diet only (27%). All patients were prospectively followed up for a period of ≤ 36 months or until occurrence of one of following CVD events: cardiac death, non fatal myocardial infarction, unstable angina requiring coronary revascularization, or ischemic stroke. During a mean follow-up of 33 months, 37 CVD events occurred (13 patients in cardiac death, 2 in acute myocardial infarction, 14 in unstable angina, 8 in ischemic stroke). Kaplan-Meier analysis demonstrated that higher RLP-C levels (≥ 4.5 mg/dL, determined by ROC-curve) resulted in a significantly higher probability for the development of CVD events than lower RLP-C levels (< 4.5 mg/dL )(p < 0.01 by log-rank test). Univariate Cox hazards analysis showed that higher levels of RLP-C, triglycerides (≥ 150 mg/dL), non-HDL-C (≥ 130 mg/dL), and apolipoprotein B (≥ 110 mg/dL, 75th percentile of the distribution) and lower HDL-C levels (< 40 mg/dL in male, < 50 mg/dL in female) were a significant predictor of CVD events. Moreover, multivariate Cox hazards model demonstrated that higher RLP-C level was the strongest predictor of CVD events (HR; 3.4, 95 %CI; 1.5 – 7.4, p < 0.01), followed by higher levels of non-HDL-C (HR; 1.6, 95 %CI; 1.1 – 8.7, p < 0.05) among covariables including triglycerides, apolipoprotein B, and HDL-C.
Conclusions: RLP-C was superior to non-HDL-C for the prediction of CVD events in patients with CAD who have achieved LDL-C goals. Remnant lipoprotein is an important target of lipid-lowering therapy after achieving LDL-C goals.