Light or regular cigarettes consumption: effect on endothelial function

Objective: To evaluate whether the effect of chronic or acute cigarette smoking on endothelial function is related to the cigarette content of tar, nicotine or carbon-monoxide (CO) reported on the pack. Methods: Cigarettes were defined as “light” or “regular” on the basis of the concomitant presence of tar, nicotine and CO above or below 7, 0.7 and 7 mg, respectively. Brachial artery flow mediated dilation (FMD) of 45 consumers of light cigarettes was compared to that of 45 consumers of regular cigarettes, matched for age, gender and pack-years. Forty-five never smokers, matched for age and gender, were included as negative controls. The acute effect of a light or a regular cigarette on FMD was assessed in 81 smokers, who were asked to smoke a single light (n=52) or regular (n=29) cigarette. In these subjects, FMD was measured before and 10 minutes after the single cigarette smoking. Results: When chronic effect was considered, FMD of light (2.78±3.13%) and regular (4.03±2.93%) cigarettes consumers were lower than in never smokers (6.26%±3.21; both p<0.002). In contrast, no difference was observed when light and regular cigarettes consumers were compared (p=ns). When acute effect was considered, a single cigarette smoking caused an FMD reduction of about 39% (p<0.0001). In this case, light and regular cigarettes had a different effect: the FMD reduction induced by a single light cigarette (5,91% ± 3,81 vs 3,22% ± 2,66) was lower than that induced from a single regular cigarette (5,87% ± 4,03 vs 4,08% ± 2,93) (p= 0.028). Conclusions: Even if a single light cigarette seems to induce a lower change in FMD than a regular cigarette, both types of cigarettes show the same detrimental effect when chronic exposure is considered. Therefore, light cigarettes consumption should not be considered a valid alternative to smoking cessation. Funding: Research was supported in part by Philip Morris USA Inc. and Philip Morris International.