Influence of simvastatin, fenofibrate and/or ezetimibe on correlation of low-density lipoprotein and nonhigh-density lipoprotein cholesterol with apolipoprotein B in mixed dyslipidemic patients.

OBJECTIVES: Correlations between low-density lipoprotein cholesterol (LDL-C), or nonhigh-density lipoprotein cholesterol (non-HDL-C) and apolipoprotein B (Apo B) change after statin therapy has been initiated in hypercholesterolemic patients. This post-hoc analysis studied the correlation between these parameters in patients with mixed dyslipidemia before and after receiving lipid-lowering treatment. RESULTS: Data from two randomized, double-blind studies of 1112 patients with mixed dyslipidemia receiving treatment (ezetimibe 10 mg, ezetimibe/simvastatin 10/20 mg, fenofibrate 160 mg, ezetimibe + fenofibrate 10/160 mg, or ezetimibe/simvastatin + fenofibrate 10/20/160 mg) were pooled. Correlation analyses and simple linear regression analyses were performed at baseline in untreated patients and after 12 weeks of treatment in the whole pooled population, the treatment groups, and after stratification by baseline triglyceride levels (150-250, ≥ 250 mg/dL) within the treatment groups. Both LDL-C and non-HDL-C were closely correlated with levels of Apo B at baseline, and these correlations improved after treatment. When using the fitted simple linear regression equations, we found that the on-treatment LDL-C and non-HDL-C levels corresponding to an Apo B of 90, 80, and 70 mg/dL were lower than proposed LDL-C and non-HDL-C treatment targets. For TG ≥ 250 mg/dL, the corresponding LDL-C was generally lower than that for triglycerides 150-250 mg/dL, except in the cases with fenofibrate in the treatment. CONCLUSION: The results of these analyses suggest that achieving goal-specified levels of Apo B in statin-treated patients with mixed dyslipidemia would require more aggressive LDL-C lowering to achieve the greatest reduction in LDL particle number.