Long-term effects of cigarette smoking and moderate alcohol consumption on coronary artery diameter. Mechanisms of coronary artery disease independent of atherosclerosis or thrombosis?

Epidemiologic studies have shown that cigarette smoking (increased risk) and moderate alcohol consumption (decreased risk) have opposite effects in coronary artery disease. To investigate whether they act via the common mechanism of affecting the coronary diameter, 31 white men with arteriographically normal coronary arteries were evaluated. Histories of cigarette smoking (never smoked, exsmoker, or current smoker) and alcohol consumption (nonuser or low user versus moderate users with an average of one drink per day) were analyzed for an association with coronary diameters. Nonsmokers had larger left main and left anterior descending diameters than either exsmokers or current smokers (p = 0.0001 and 0.004). Moderate alcohol users had large left main and left anterior descending diameters than nondrinkers (p = 0.009 and 0.01). Neither association was removed after adjustment for the other risk factor. These data suggest that smoking and moderate alcohol use have significant, independent, and opposite effects on long-term coronary diameter. These effects may be important mechanisms through which these behaviors alter the risk of coronary artery disease.