Body composition and fat repartition in relation to structure and function of large arteries in middle-aged adults (the SU.VI.MAX study)

OBJECTIVE: To investigate associations of body composition assessed by bioimpedance analysis and anthropometric indicators of fat repartition with carotid structure and function. DESIGN: Cross- sectional epidemiological study. SUBJECTS: A total of 1014 middle-aged apparently healthy adults participating in the SU.VI.MAX study. MEASUREMENTS: Body composition (fat mass, fat- free mass) was assessed by bioimpedance analysis and anthropometric indicators of fat repartition (waist circumference (WC); waist- hip- ratio (WHR)) were simultaneously collected. Carotid ultrasound examination included measurements of intima- media thickness (IMT) at the common carotid arteries (CCA) and assessment of atherosclerotic plaques in extracranial carotid arteries. Carotid-femoral pulse-wave velocity (PWV) was used as a marker of aortic stiffness. RESULTS: In multivariate analyses adjusted for major known cardiovascular risk factors in addition to age, gender and height, fat-free mass, fat mass (FM), and WC were positively associated with CCA-IMT and lumen diameter. No significant association was found with occurrence of carotid plaques. PWV was only associated with WC. Associations of CCA-IMT and PWV with WC were not significant anymore after further adjustment on body mass index (BMI) or FM. CONCLUSION: WC was the only measurement positively associated with both early atherosclerosis markers such as CCA-IMT and arterial stiffness. Although this association depends on overall adiposity, as assessed by the BMI, it emphasizes the importance of WC in clinical practice and prevention programs as a screening tool for individuals at risk for cardiovascular disease.