The apolipoprotein story

The importance of different lipid and lipoprotein measurements, including LDL particle concentration and levels of apolipoproteins and triglycerides, in the prediction of future cardiac events continues to be debated. In summary, apo B is a strong, independent predictor of initial and recurrent coronary events, even during statin treatment, and recent studies show its predictive superiority over LDL and non-HDL cholesterol. Importantly, determination of apo B levels is unaffected in a non-fasted or hypertriglyceridemic state and is not derived from other measurements. Thus, clear advantages exist for using apo B as a predictor of CHD. Likewise, triglycerides and triglyceride-rich lipoproteins are also strong, independent predictors of coronary events (initial and recurrent) during statin treatment. Triglycerides or especially triglyceride-rich lipoproteins with apo C-III may provide additional information to apo B. Apo C-III not only impairs lipoprotein metabolism but also stimulates directly the vascular inflammatory process. In contrast, evidence from large epidemiological studies is coalescing toward the view that small LDL size is more of a marker of these atherogenic triglyceride-rich lipoproteins than an independent predictor of CHD. Clearly, there remains considerable interest, both in terms of research and clinical practice, in the role of apo B, triglycerides, and specific apo B-containing lipoprotein particles as independent predictors of CHD risk as well as their potential to improve risk prediction and response to lipid-modifying treatment.