Relationship between coronary artery disease and non-HDL-C, and effect of highly purified EPA on the risk of coronary artery disease in hypercholesterolemic patients treated with statins: sub-analysis of the Japan EPA Lipid Intervention Study (JELIS).

Aim: The present study examined the importance of reducing non-high-density lipoprotein cholesterol (non-HDL-C) for the primary prevention of the occurrence of coronary artery disease (CAD) in the JELIS, and the effects of EPA.
Methods: The patients were distributed into 4 subgroups using the lipid management goal for LDL-C recommended by the Japan Atherosclerosis Society guideline (2007) and the goal for non-HDL-C defined as 30 mg/dL higher than LDL-C: A) achieved both goals; B) achieved the LDL-C but not non-HDL-C goal; C) achieved the non-HDL-C but not LDL-C goal; and D) did not attain either goal. The incidences of CAD in the 4 subgroups were compared, and the effects of eicosapentaenoic acid (EPA) on the risk of CAD in these subgroups were examined.
Results: In the non-EPA group, the incidence of CAD in patients who did not achieve the goals for LDL-C or non-HDL-C was higher than in patients who achieved those goals. Patients in subgroups B, C, and D were at higher risk for CAD than those in subgroup A (B, HR 2.31; C, HR 1.90; D, HR 2.47). EPA reduced the risk of CAD by 38% in subgroups B, C, and D (p= 0.007).
Conclusion: We reconfirmed non-HDL-C as a predictor of the risk for CAD and a residual risk marker of CAD after LDL-C-lowering therapy. EPA was useful to reduce the occurrence of CAD in patients who did not achieve the goals for LDL-C and/or non-HDL-C.