Robert Roberts
Plasma low-density lipoprotein cholesterol (LDL-C) is the main cause of coronary artery disease (CAD). All cells synthesize their own cholesterol when needed to form membranes for the cell wall and other cellular structures, including the synthesis of vitamin D. Cholesterol in excess of the cell's needs is dumped into the bloodstream to be metabolized by the liver and secreted into the intestine. Of the circulating cholesterol, 80% is derived from this excessive endogenous cholesterol, with only a small proportion from diet. Thus, it is not surprising that lowering plasma LDL-C to levels as low as 5 to 10 mg/dL is associated with further reduction in cardiac events and no apparent increase in adverse events. Individuals at increased risk for CAD should embrace a more favorable lifestyle and simultaneously be started on a lipid-lowering agent, which initially should be a statin. Taken by hundreds of millions of patients for over three decades, statins are highly efficacious and safe and are said to be safer than aspirin. Although the plasma LDL-C level for optimal efficacy and safety has yet to be determined, the future goal is likely to be around 40 mg/dL, a level observed in infants.