Serum cholesterol as a risk factor for coronary heart disease revisited

The biology of lipoproteins and lipoprotein particles as mediators of atherosclerosis has been documented extensively. Numerous prospective epidemiological studies have shown a robust relationship between low-density lipoprotein (LDL) cholesterol, or particles bearing apolipoprotein B, and increased risk of coronary heart disease (CHD); and between high-density lipoprotein (HDL) cholesterol or particles bearing apolipoprotein A1, and decreased risk. These relationships are present across the age spectrum and in both sexes. The causality of LDL cholesterol for CHD has been established by the clinical trials on cholesterol lowering and the Mendelian randomisation studies. However, clinical trials that focus on raising HDL cholesterol, or lowering triglycerides, have yielded mixed results, and the Mendelian randomisation studies have generally not supported causality. Research on the effects of diet on serum cholesterol led to public health guidelines, whose implementation withinthe last five decades was accompanied by lower population cholesterol levels and CHD burden in all of the countries studied. Over the last three decades, the favourable trends in cholesterol levels and CHD have been supported by the increasing use of statin drugs and improved treatments for myocardial infarction