Alcohol and stroke.

Alcohol might contribute to stroke in several ways: induction of cardiac arrhythmias and cardiac wall motion abnormalities which predispose to cerebral embolism, induction of hypertension, enhancement of platelet aggregation and activation of the clotting cascade, and reduction of cerebral blood flow by stimulation of cerebral vascular smooth muscle contraction or by altering cerebral metabolism. While these pathophysiological mechanisms have gained enthusiastic experimental and theoretical support, the findings are preliminary and will require further large-scale clinical and epidemiological analyses to substantiate their roles as causal factors or potentiators of stroke. Documentation of measurable platelet and coagulation cascade abnormalities reported in healthy volunteers who have ingested alcohol will need to be confirmed on a broader scale in stroke patients with recent ethanol consumption. The risk of stroke in those with alcohol-induced atrial fibrillation and cardiomyopathy must be ascertained for the general population. While the experimental evidence is exciting and provocative, epidemiological evidence also suggests a link between alcohol consumption and stroke. Regular alcohol ingestion is associated with hypertension, fatal and nonfatal intracranial hemorrhage, cerebral infarction, and increased risk of death from stroke. Recent, less stringently controlled studies suggest that alcohol consumption is a risk factor for cerebral infarction in young adults with occasional ethanol intoxication and middle-aged women and young men with occasional alcohol intoxication and regular heavy drinking. Alcohol may also be a risk factor for subarachnoid hemorrhage.