HDL-c is a powerful lipid predictor of cardiovascular diseases.

RELATIONSHIP BETWEEN HDL-C AND CARDIOVASCULAR DISEASES: Beyond the role of low-density lipoprotein cholesterol (LDL-c) in the development of atherosclerosis, growing evidence suggest that high-density lipoprotein cholesterol (HDL-c) is a powerful predictor of cardiovascular disease. Indeed, epidemiological, mechanistic and intervention studies suggest that low HDL-c is a major cardiovascular risk factor and that increasing HDL-c plasma levels may be beneficial, particularly in patients with low HDL-c levels. The inverse association between HDL-c concentrations and cardiovascular risk is continuous without threshold value. Thus, any categorical definition of low HDL-c is arbitrary. PROTECTIVE EFFECTS OF HDL: HDL particles are highly heterogeneous in structure and intravascular metabolism. Antiatherogenic properties of HDL include its role in the reverse cholesterol transfer, besides its antioxidant, anti-inflammatory and antiapoptotic activities. WHAT SHOULD CLINICIANS DO?: From a practical point of view, HDL-c should be systematically measured to assess the cardiovascular risk in patients. The first step to consider in subjects with low HDL-c is to look for specific causes and give advice to change inappropriate lifestyle components associated with low HDL-c, such as smoking, lack of physical exercise and overweight. Patients with very low HDL-c need a thorough evaluation by specialist physicians. Statins are associated with a modest increase of HDL-c (5%) while fibrates and nicotinic acid increase HDL-c by 10% and 20% respectively.