Endocrine Abstracts

Background: The clustering of metabolic and cardiovascular risk factors is known as the metabolic syndrome (MetS). Lifestyle factors like smoking may contribute to the differences in prevalence of the MetS. The aim of this study was to examine the association between smoking and the MetS and its components in different BMI classes.

Methods: The present cross-sectional evaluation comprised 24 762 men and 35 558 women, participating in the LifeLines Cohort Study, of whom 6,058 and 7,469 were current smokers. MetS was defined using the criteria of the NCEP ATP III. Participants were categorized in different BMI classes (i) BMI <25; ii) BMI 25–30; iii) BMI >30 kg/m²). Linear regression was used to test the association between smoking and the components of MetS, stratified by gender and age.

Results: There was an increasing prevalence of MetS with increasing BMI. In obese men (BMI ≥30 kg/m²) 62% fulfilled the MetS criteria, for women this was 41%. Overall, current smoking was associated with increased risk for MetS in both genders and all BMI classes (OR’s 1.7–2.4 for men, 1.8–2.3 for women, all P<0.001). In all BMI classes, there was a dose-dependent association between the amount of tobacco smoked daily and the prevalence of MetS. Compared to non-smokers, current smokers had lower levels of HDL cholesterol, and higher levels of triglycerides and waist circumference in all BMI-classes (all P<0.001). Smoking had no consistent association with blood pressure or fasting blood glucose levels. We observed a dose-dependent association between the amount of tobacco smoked daily and lower HDL cholesterol and higher triglyceride levels in normal weight, overweight and obese smokers (all P<0.001).

Conclusions: Smoking is associated with an increased risk for the metabolic syndrome, in all BMI classes. This increased risk was mainly related to lower levels of HDL cholesterol, and increased triglycerides and waist circumference.