Smoking Can Knock Out Benefits of Alcohol on Stroke Risk

It seems clear that regular light-to-moderate alcohol intake (up to 1 drink a day for women, two for men) can have a small but significant protective effect on the occurrence of stroke.  And smoking has a deleterious effect on the risk.  So the results of a new UK study which evaluates the effects of drinking in smokers is of considerable interest.  These were reported at the American Academy of Neurology meeting this month. 

This was a prospective study in 10,000 men and 12,300 women aged 40 to 80, who were followed for 12 years.  During this time 864 of them had a stroke.  It was found that mild to moderate alcohol use reduced the risk of stroke, but heavy drinkers had an increasing risk in proportion to the amount they drank.  The nadir, or bottom, of this J-shaped curve was reached with 7 to 14 drinks a week. 

Further, in this study the protective effect at moderate intake levels was absent in cigarette smokers.  This suggests that smoking may modify the relationship between alcohol intake and stroke risk.  It must be noted, however, that other studies have confirmed the benefit of moderate alcohol, but failed to find this benefit was absent in smokers.