Unlike coronary heart disease, epidemiologic studies find a weak and inconsistent relationship between cholesterol levels and overall stroke risk. There does, however, appear to be a positive relationship between total and low-density lipoprotein cholesterol levels and the risk of ischemic stroke, with an inverse relationship between cholesterol levels and hemorrhagic stroke. Treatment with statins is associated with the reduction in the risk of a first stroke in various populations of patients at increased risk of cardiovascular events. Treatment of patients with prior cerebrovascular disease is associated with a reduction in major cardiovascular events and, in a single study, with a reduction in fatal and nonfatal stroke in patients with prior stroke or transient ischemic attack and no known coronary heart disease. Whether the benefit of statins in reducing the risk of stroke is due to their potent lipid-lowering effects, pleiotropic effects, or a combination of the two cannot be determined based on data available from clinical trials.