Impact of cigarette smoking on the plasma fatty acid profile and their interaction in determining the burden of subclinical atherosclerosis

Background and aims: Cigarette smoking is a well established determinant of carotid atherosclerosis. The mechanisms potentially responsible of this effect, e.g. activation of extensive peroxidation processes leading to, among others, altered endothelial function, may involve changes of fatty acid (FA) levels. In this study we evaluated the impact of cigarette-smoking on FA profiles and interactions with circulating FAs in determining subclinical atherosclerosis. This was established by the parallel determination of the carotid intima-media thickness (C-IMT). Methods and Results: Plasma FA composition and C-IMT were measured in 36 Smokers and 36 Never-smokers, matched for age, sex and lipid levels. Compared to never-smokers, smokers had higher saturated FA (14:0, 16:0) and monounsaturates FA (16:1, 18:1) levels and lower levels of 24:1, arachidonic acid, docosahexaenoic acid, total poly unsaturated fatty acids and n-3. Endogenously generated FA (e.g. docosapentaenoic acid) and the 5 Desaturation Index were also reduced in smokers. In partial correlation analysis of the whole series of 72 subjects, after adjustment for BMI and triglycerides, C-IMT correlated positively with 18:3 n-6, eicosapentaenoic acid and 6 Desaturation Index and negatively with 20:1, linoleic acid, and n-6. When the analysis was carried out separately in smokers and never-smokers, correlations retained significance only in smokers. Conclusions: Cigarette-smoking has an impact on the FA profile and may influence the different correlations between plasma FA and subclinical atherosclerosis observed in smokers and never-smokers.