CONSUMO DI SIGARETTE LEGGERE O PESANTI: EFFETTO COMPARATIVO SU MARKERS MORFOLOGICI E FUNZIONALI DI ATEROSCLEROSI

BACKGROUND: Mistaken beliefs about the possible benefits of light cigarettes are still widespread even in countries where considerable efforts have been made to educate population about the misconception of \u2018\u2018light\u201d. Many smokers, in fact, use light cigarettes in the belief that this may reduce the risks for health or as a first step toward stopping smoking. However little is known on whether light and regular cigarettes have different effects on morphological and functional markers of subclinical atherosclerosis. AIM: In the present study we have evaluated whether the effect of chronic or acute cigarette smoking on carotid atherosclerosis and endothelial function is related to the cigarettes' content of tar, nicotine or carbon-monoxide reported on the pack. METHODS: 1804 patients (869 men, age 21 to 85 year) participated in the study. Smoking habits were recorded and carotid intima media thickness (IMT) was measured by B-mode ultrasound. The associations of IMT with smoking status (never, former, and current) and with the cigarettes\u2019 content of tar, nicotine, and carbon monoxide (alone or combined to define light or regular cigarettes) as well as the interactions between smoking status, gender, and vascular risk factors were evaluated before and after adjustment for confounders. In a subgroup of 206 subjects, brachial artery flow mediated dilation (FMD) was measured by B-mode ultrasound. The chronic and acute effect on FMD of light or regular cigarettes was evaluated before and after adjustment for confounders. The chronic effect was assessed in 53 consumers of light cigarettes, 85 consumers of regular cigarettes and 68 never smokers. The acute effect was assessed in 51 and 29 smokers, who smoked a single light or regular cigarette, respectively. In these subjects, FMD was measured before and 10 min after smoking. RESULTS: IMT was highest in current smokers, lower in former, and lowest in never smokers. IMT of former and current smokers differed only after data adjustment for variables describing the extent and timing of smoking exposure. IMT was positively related to the number of pack-years (number of cigarettes smoked per day multiplied by number of years smoked/20) in both former and current smokers. There were no differences in IMT between smokers of cigarettes with high or low nicotine, tar, or carbon monoxide content. Both diabetes and hypertension interacted positively with smoking in determining IMT. When compared to FMD of never smokers, chronic consumption of both light and regular cigarette was associated with reduced FMD. No difference between FMD of light and regular cigarettes consumers was observed (p>0.05). Both types of cigarettes acutely reduced FMD (p