[What is a good marker for serum cholesterol to identify high-risk patients at general health checks?].

Conventional measurement of lipid concentrations includes total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), and triglycerides (TG). Several guidelines for cardiovascular diseases recommend using LDL-C as the primary target of therapy in conjunction with assessing risk factors for cardiovascular diseases (CVD); however, emerging findings have revealed that lowering LDL-C to the goal with statins is not enough to prevent primary and secondary CVD. Thus, we need new parameters to better integrate residual risks into CVD risk stratification. Recently, non-HDL-C, apolipoprotein B (apoB), and LDL-C/HDL-C have been suggested. Non-HDL-C, indicating the cholesterol contents of all atherogenic lipoproteins and retaining continuity with the concept of cholesterol, is quickly computed by subtracting HDL-C from TC, needs no additional costs, and includes atherogenic TG-rich lipoproteins, called remnant lipoproteins. In addition, non-HDL-C has been shown to be an excellent predictor of CVD, free from dietary variations. ApoB, the number of atherogenic lipoproteins, is also a valuable parameter with slightly better performance than non-HDL-C in epidemiological studies, but it costs more and takes longer than conventional lipid examinations. Several lipid parameters, such as TC/HDL-C, non-HDL-C/HDL-C, LDL-C/HDL-C, are also available in clinical practice and epidemiological study; however, we should note that LDL-C/HDL-C is not reliable in cases of high TG. Thus, in general health checks, we should first pay attention to the absolute values of LDL-C, HDL-C, and TG for the diagnosis and subsequently use non-HDL-C, apoB, and other parameters, considering the pathophysiological condition, convenience, and costs.