Serum high density lipoprotein cholesterol level and risk of death: let’s avoid the extremes
Cardiovascular disease (CVD) continues to be the major cause of death worldwide, with dyslipidemia as a well-known primary target and modifiable risk factor (1). Numerous observational studies found that the risk of CVD and mortality is inversely associated with serum levels of HDL-C in several patient populations including those with and without CVD (2). Thus, a consensus has formed over the past few decades that low serum HDL-C levels can serve as a marker of risk for adverse events whereas increasing concentrations of HDL can be considered protective. In addition, major efforts were undertaken to devise strategies aimed at increasing serum HDL-C concentrations as a means for reducing CVD and thereby overall mortality. However, several large randomized clinical trials using pharmacologic agents such as niacin and cholesterol ester transfer protein (CETP) inhibitors to increase serum HDL-C levels were not proven to be effective in reducing the risk of mortality (3-5).