The clinical relevance of LDL size and subclasses modulation in patients with type-2 diabetes

Increasing evidence suggest that the "quality" rather than only the "quantity" of low density lipoproteins (LDL) exerts a great influence on the cardiovascular risk. Hypertriglyceridemia, low HDL-cholesterol and increased levels of small dense LDL characterise diabetic dyslipidemia. In subjects with type-2 diabetes LDL size seems also to represent a good marker of clinical apparent and non-apparent atherosclerosis. Recently, the Coordinating Committee of the National Cholesterol Education Program stated that high-risk patients may benefit of stronger therapeutical approaches, a category of subjects that include those with type-2 diabetes. Screening for the presence of small, dense LDL may potentially identify those with even higher risk and may contribute in directing specific treatments in order to prevent new cardiovascular events. Hypolipidemic treatments are able to favourably modulate LDL size and subclasses in patients at higher cardiovascular risk. Regarding subjects with type-2 diabetes this seems particularly true for fibrates and less for statins. Analysis of all published studies revealed that atorvastatin represents the most effective agent among statins, while fenofibrate, bezafibrate and gemfibrozil are all very beneficial in modifying LDL size and subclasses towards less atherogenic particles. Nicotinic acid has been found also effective but the extended-release form should be preferred for the reduced intolerance, while fish oils have been shown to be less beneficial. Promising data are also available with the use of ezetimibe, a cholesterol absorption inhibitor.