Cardiovascular diseases remain the predomnant cause of morbidty and mortality in the world mainly because of atherosclerosis, which is determined by several factors, including plasma lipoproteins. The most import ant are low-density lipoproteins, which stimulate retention of cholesterol in artery wall, and high-density lipoproteins, which have an antiaterogenic effect. The guidelines of the European Atherosclerosis Society and the European Society of Cardiology recommend to evaluate the level of low and high density lipoproteins by concentration of cholesterol, but more evidence emerges about other important indicators.
In case of insulin resistance smaller, denser low-density lipoproteins appear in the bloodstream. These particles have more prominent role in progression of atherosclerosis compare to regular size low-density lipoproteins because of their ability to penetrate subendothelial space more easily, stronger binding to proteoglycans and their higher susceptibility to oxidation and glycolysation. High-density lipoproteins may be bigger, less dense with stronger antiaterogenic effect, or smaller, denser, which are more common in cardiovascular diseases. In some conditions with elevated high-density lipoprotein concentration, due to the changes in structure of protein and lipid components, dysfunctional high-density lipoproteins are formed, which lose antiaterogenic efect and even stimulate atherosclerosis. Another important factor is lipoprotein(a) - low-density lipoprotein - like plasma lipoprotein. Lipoprotein(a) is an independent risk factor for cardiovascular diseases, important because of its proaterogenic, antifibrinolytic effect.
Therefore, for the risk assessment in cardiovascular diseases it is proposed to determine not only low or high-density lipoprotein cholesterol concentrations, but also include measurements of apolipoprotein B, which reflects the amount of atherogenic particles, high-density lipoprotein function and lipoprotein (a) concentration.
