The metabolic syndrome as a link between smoking and cardiovascular disease

Objective: Smoking is associated with a significant increase in the cardiovascular risk. The possible relationship of smoking with insulin resistance might further enhance the cardiovascular risk of the patients and is therefore of great clinical interest. Design, Setting and Subjects: We have retrospectively evaluated data of 3804 non-diabetic men attending a medical outdoor clinic. Clinical [body mass index (BMI), percentage of body fat, waist-to-hip ratio] and laboratory results were compared between smokers (n = 124) and non-smokers (n = 1915) without cardiovascular disease, as well as between smokers (n = 759) and non-smokers (n = 1006) with cardiovascular disease. Results: Smokers without clinically manifest cardiovascular disease revealed significantly higher fasting glucose (5.8 +/- 0.6 mmol/l) and triglyceride levels (1.8 +/- 0.9 mmol/l) than non-smokers (fasting glucose: 5.1 +/- 0.7 mmol/l, p < 0.010; triglycerides: 1.5 +/- 0.8 mmol/l, p < 0.030). The adverse metabolic profile of smokers was even more pronounced in patients with cardiovascular disease. An age-matched analysis of smokers could demonstrate that cardiovascular patients revealed higher BMI values (27.3 +/- 2.4 kg/m(2)) and a higher percentage of body fat (25.5 +/- 5.5%) than those without cardiovascular disease (BMI: 25.7 +/- 2.2 kg/m(2), p < 0.010; percentage of body fat: 23.0 +/- 5.5%, p < 0.030). Conclusion: In men with and without clinically manifest cardiovasular disease, smoking was associated with a metabolic profile indicating a higher degree of insulin resistance.