Reduction of the Nailfold Capillary Blood Velocity in Cigarette Smokers

BACKGROUND Cigarette smoking causes cardiovascular disease and activates markers of endothelial dysfunction or injury. We investigated the nailfold capillary blood velocity (NCV) in cigarette smokers compared to non-smokers. METHODS Forty-eight men (eighteen non-smokers and thirty smokers) were recruited. We measured NCV using nailfold capillary microscopy and exhaled carbon monoxide (ECO) concentration three times (before smoking; NCV(0min) and ECO(0min), and after smoking; NCV(5min), ECO(5min), NCV(30min), and ECO(30min)), in a condition of fasting in the case of smokers. In non-smokers, the same measurements were taken without smoking. Additionally, personal cigarette smoking and alcohol drinking history were acquired by a self-administrated questionnaire. RESULTS Mean age, waist circumference, ECO(0min), ECO(5min), and ECO(30min) was higher and NCV(5min) and NCV(30min) were significantly lower in smokers compared to non-smokers. Total smoking years were negatively correlated with NCV(5min). Average pack of the daily smoking, total pack-years, as well as total smoking years were also negatively correlated with NCV(30min) by regression analysis. After adjustment of significantly different variables, NCV(30min) was significantly lower in smokers. In the subgroup analysis, the interleukin-6 level was significantly increased in subjects with a long period of cigarette smoking compared with non-smokers. CONCLUSION Reduction of NCV in smokers is associated with personal smoking history, not with body composition or certain oxidative stress markers.