Beyond LDL-C--the importance of raising HDL-C.

Epidemiological studies have established that low levels of high-density lipoprotein cholesterol (HDL-C) are associated with an increased risk of coronary heart disease (CHD). Recent studies have demonstrated that low HDL-C levels, and high triglycerides and total cholesterol levels are independent predictors of CHD, and that the combination of these lipid abnormalities increases the risk of coronary events. In lipid-modifying intervention studies, agents that raise HDL-C levels have been shown to reduce the incidence of major coronary events. The VA-HIT study consisted of patients with low-density lipoprotein cholesterol (LDL-C) levels similar to those recommended by several guidelines but with low levels of HDL-C. This trial demonstrated that raising HDL-C levels with gemfibrozil reduced the risk of CHD-related events. While the mechanisms by which HDL-C exerts its anti-atherogenic effects have yet to be fully elucidated, its role in the reverse transport of cholesterol and the beneficial effects on endothelial function are plausible explanations for these actions. Although LDL-C reduction is the primary goal in the treatment of dyslipidaemia, current guidelines recognise low HDL-C levels as a major risk factor for CHD. Indeed, the NCEP ATP III guidelines suggest that the treatment of isolated low HDL-C levels in CHD patients or individuals with CHD risk equivalents should be considered. The differing abilities of statins to raise HDL-C levels may be an important factor when making treatment decisions. New lipid-modifying drugs with beneficial effects on both HDL-C and LDL-C levels would be desirable additions to the currently available therapeutic options.