Switching from statin monotherapy to ezetimibe/simvastatin or rosuvastatin modifies the relationships between apolipoprotein B, LDL cholesterol, and non-HDL cholesterol in patients at high risk of coronary disease

Update on the NCEP ATP-III emerging cardiometabolic risk factors

The intent of this review is to update the science of emerging cardiometabolic risk factors that were listed in the National Cholesterol Education Program (NCEP) Adult Treatment Panel-III (ATP-III) report of 2001 (updated in 2004). At the time these guidelines were published, the evidence was felt to be insufficient to recommend these risk factors for routine screening of cardiovascular disease risk. However, the panel felt that prudent use of these biomarkers for patients at intermediate risk of a major cardiovascular event over the subsequent 10 years might help identify patients who needed more aggressive low density lipoprotein (LDL) or non-high density lipoprotein (HDL) cholesterol lowering therapy. While a number of other emerging risk factors have been identified, this review will be limited to assessing the data and recommendations for the use of apolipoprotein B, lipoprotein (a), homocysteine, pro-thrombotic factors, inflammatory factors, impaired glucose metabolism, and measures of subclinical atherosclerotic cardiovascular disease for further cardiovascular disease risk stratification.

Effects of ezetimibe, simvastatin and ezetimibe/simvastatin on correlations between apolipoprotein B, LDL cholesterol and non-HDL cholesterol in patients with primary hypercholesterolemia

BACKGROUND/SYNOPSIS

Apolipoprotein (apo) B is highly predictive of coronary risk, especially in patients with high triglycerides (TG). This post hoc analysis evaluated the effects of lipid-lowering therapy on correlations between apoB and low-density lipoprotein cholesterol (apoB:LDL-C) and non-high-density lipoprotein cholesterol (apoB:non-HDL-C) in patients with TG< and ≥ 200 mg/dL.

METHODS

This analysis used data from 3 randomized clinical trials in patients with primary hypercholesterolemia receiving placebo, ezetimibe (EZE), simvastatin (SIMVA) or EZE/SIMVA for 12 weeks. Simple linear regression analyses predicted LDL-C and non-HDL-C levels corresponding to apoB values (80 mg/dL) at baseline and Week 12.

RESULTS

ApoB correlated with LDL-C (r ≥ 0.76) and non-HDL-C (r ≥ 0.86) at baseline. The correlations were strengthened with SIMVA and EZE/SIMVA at Week 12 (r ≥ 0.88 for LDL-C and r ≥ 0.94 for non-HDL-C). The predicted LDL-C and non-HDL-C values were lower following treatment with SIMVA or EZE/SIMVA than for placebo and EZE. For SIMVA and EZE/SIMVA, the predicted LDL-C and non-HDL-C values were closer to more aggressive LDL-C and non-HDL-C levels (i.e., 70 and 100 mg/dL, respectively). The apoB:LDL-C and apoB:non-HDL-C correlations were weaker and the predicted LDL-C values were generally lower in high TG patients than in low TG patients both at baseline and Week 12. In contrast, the predicted non-HDL-C values were generally higher in high versus low TG patients at baseline but less so at Week 12.

CONCLUSION

After treatment with EZE, SIMVA, or EZE/SIMVA, a given apoB value corresponds to lower LDL-C and non-HDL-C levels than those obtained from untreated patients.