SMOKING HABITS AS DETERMINANT OF CAROTID IMT IN PATIENTS IN PRIMARY AND SECONDARY PREVENTION

Objective: To compare the contribution of smoking habit as determinant of carotid artery intima media thickness (IMT) in patients symptomatic for vascular disease and asymptomatic controls. Methods: Patients in secondary prevention (SP) were matched for gender and smoking habit with patients classified in primary prevention (PP) because free of vascular events even if ten years older (n=180 per group). In both groups there were 87 never-, 68 former- and 25 current-smokers. Results: Years of smoking, cigarettes/day (cig/die) and pack-years correlated with IMT better in SP than in PP patients. In former smokers, a stronger negative correlation with years elapsed since smoking cessation was observed in SP than in PP patients. Although selected to be 10 years older, patients in PP showed a lower IMT than those in SP (0.93±0.33 vs 1.06±0.34; p=0.009). Similar results were obtained after patients stratification in never-, former and current-smokers. A general linear model confirms, after data adjustment for age, cig/die and conventional vascular risk factors, that both prevention level (p=0.012) and smoking habits (p=0.017) were independently associated with carotid IMT. No additive effect between prevention level and smoking habits was observed. Conclusions: Prevention level is associated with a thickened carotid intima media complex independently of variables descriptive of smoking behaviour and other conventional risk factors. Smoking habit is an important determinant of carotid IMT both in primary and secondary prevention patients. Funding: Research supported in part by Philip Morris USA Inc. and Philip Morris International.