Forearm endothelial response in smokeless tobacco users compared with cigarette smokers and nonusers of tobacco.

Study Objective: To compare brachial artery flow-mediated dilation (FMD) in subjects who use smokeless tobacco, smoke cigarettes, or do not use any tobacco product.

Design: Cross-sectional study.

Setting: University-affiliated outpatient clinic.

Subjects: Seventeen apparently healthy volunteers who for more than 1 year smoked at least 10 cigarettes/day, used at least two containers of smokeless tobacco/week, or did not use any tobacco product.

Measurements And Main Results: Baseline characteristics of subjects were similar among the three groups except for mean age and serum cotinine level. Baseline brachial artery diameter, endothelium-dependent FMD induced by reactive hyperemia, and endothelium-independent dilation induced by administration of sublingual nitroglycerin were measured. Mean FMD over baseline was 4.1% +/- 0.7% in subjects who used smokeless tobacco, 3.9% +/- 5.1% in cigarettes smokers, and 12.2% +/- 5.7% in nonusers of tobacco (p=0.01). Endothelium-independent dilation induced by nitroglycerin was not statistically different among the three groups.

Conclusion: Brachial artery FMD, a surrogate for endothelial dysfunction, was significantly impaired in smokeless tobacco users and cigarette smokers compared with nonusers of tobacco.