Cholesterol and strokes

Abstract

Strong correlations between plasma lipoprotein concentrations and the risk of stroke have never been clearly established. Unlike coronary heart disease, there is no significant direct relation between an increased risk of stroke and increased plasma total cholesterol or low density lipoprotein (LDL) cholesterol; nor is there an inverse relation with high density lipoprotein (HDL) cholesterol.1 Indeed, an inverse relation exists between total cholesterol concentrations and cerebral haemorrhage.2 The reasons for this weak or absent relation are several. The most compelling is that virtually all coronary heart disease can be ascribed to coronary atheroma, whereas less than half the incidence of stroke is due to large vessel atheroma. Non-atheromatous causes such as cardiac arrhythmias, small cerebral artery disease, and cortical degeneration are responsible for most of the rest. Another is that, in general, coronary deaths occur at a younger age than strokes, so the population with raised plasma lipids and large vessel atheroma, such as carotid artery disease, is …