What supports the role of alcohol as a risk factor for stroke?

For more than 30 years, clinical observations to link alcohol abuse and stroke have accumulated in several countries. Studies of general populations have indicated that the risk for stroke increases with increasing alcohol consumption. Studies of young victims of stroke where the classical risk factors of stroke are uncommon, have demonstrated that even occasional heavy drinking carries an increased risk for stroke. In particular, the increased occurrence of strokes during weekends, the very time of heavy alcohol consumption in non-alcoholics, supports this notion. Alcoholics seem to get their strokes at an earlier age than non-alcoholics. Paradoxically, the published evidence has implicated drinking in both ischemic and hemorrhagic strokes, which suggests that there may be more than one mechanism by which alcohol can increase the risk. Strokes seem to be precipitated during the alcohol intoxication itself rather than the following withdrawal syndrome, but the contributing mechanisms, except for bleedings caused by external violence, are unknown. Alcohol can produce fluctuations in platelet reactivity and untoward interactions with certain drugs, but it remains to be demonstrated that such effects are temporally related to the onset of ischemic and hemorrhagic strokes.