NEW YORK, Nov 09 (Reuters Health) -- Heavy drinking may greatly increase risks for stroke, researchers report.
"This is a new item on the list of hazards caused by heavy drinking of alcohol," write Finnish researchers led by Dr. Matti Hillbom from Oulu University Central Hospital in Oulu, Finland. They published their findings in the November issue of Stroke, a journal of the American Heart Association.
The researchers compared the drinking patterns of 212 hospitalized stroke patients with those of 274 patients admitted to hospital for other causes.
After adjusting for age, sex, smoking history and other factors, recent moderate or heavy alcohol intake emerged as a "significant and independent risk factor" for cardioembolic stroke in men. Cardioembolic stroke occurs when clots travel from the chambers of the heart, blocking arteries that supply the brain.
The authors report that risks for stroke rose nearly fourfold among patients who had consumed anywhere from 13 to 25 drinks in the week previous to hospital admission, compared with nondrinkers.
The investigators conclude "that (heavy) drinking of intoxicating amounts of alcohol may trigger the onset of embolic stroke." Increases in risk applied only to current heavy drinkers, not to patients with a previous history of heavy drinking or light drinkers.
The Finnish researchers speculate that heavy drinking may encourage cardiac arrhythmia -- an irregular heart rhythm that raises risks for blood clots. They point to the case of one 37-year-old man with a previous history of arrhythmia who suffered "two separate... strokes during acute alcohol intoxication." Regular heavy drinking may also lead to a deterioration of heart muscle known as cardiomyopathy.
Finally, the authors point out that drinking binges can exacerbate sleep apnea (closure of the airway during sleep) or vomiting -- both of which are linked to increased stroke risk.
