Hydroperoxides and cytokines as biomarkers in detecting atherosclerosis predisposition in cigarette smokers

Objectives: Smoking increases oxidative modification of LDL, associated with lower HDL plasma levels, systemic inflammatory response and endothelial dysfunction. We tested the hypothesis that the risk status for coronary atherosclerosis disease (CAD) of cigarettes smokers might be identified by means of serum oxidative levels and vascular inflammation determination. Design and Methods: Oxidative stress levels, cytokines, and the metabolic status were investigated on 499 subjects admitted to our institute. The association between biomarkers and smoking habits in the presence/absence of disease and with the number of vessel affected, was studied. Results: Oxidative stress and inflammatory levels (p < 0.001) were strongly induced by smoking habits. Serum values of the subjects categorised as CAD, non CAD and healthy subjects differed significantly (p < 0.001) only for the degree of oxidative stress. Glycaemia was able to affect C-reactive protein serum levels with a positive association (p < 0.05). The analysis of the study population indicated that serum oxidative stress levels significantly increased with increasing number of vessels affected (p < 0.01). When statistical analysis was performed separately in both smoking groups, smokers did not show any particular difference for both oxidative stress and inflammation markers between the two groups of cardiovascular patients (CAD and non CAD) and the control group, while for non smokers, the differences were evident. Conclusion: These findings indicate that the considered biomarkers, especially oxidative stress, can be useful to predict the biological damage caused by cigarette smoking, as well as to identify subjects characterised by a higher risk of cardiovascular event, but cannot evaluate the presence of disease in subjects with smoking habit.