Context: An independent association between obesity and preclinical carotid atherosclerosis has been demonstrated, however the pathophysiologic links were not clearly established. Body composition (BC) influences systemic hemodynamics and may participate on remodeling of common carotid artery (CCA), independently of risk factors.

Objective: This study evaluated the association between CCA structure and BC in a large population of healthy subjects.

Design: This was a cross-sectional study.

Settings: The study was conducted at 19 European centers.

Subjects: The study included 627 healthy subjects (252 men, age 30–60 years, BMI 17–40 kg/m²).

Main Outcome Measures: CCA luminal diameter and intima-media thickness (IMT) were measured in digitized ultrasound images. Acoustic properties of CCA wall were evaluated by digital densitometric analysis and described in terms of mean grey level (MGL). BC was assessed by electrical bioimpedance. Insulin sensitivity (euglycemic hyperinsulinemic clamp) and plasma adiponectin levels were measured. Associations between CCA structure, age, BC, metabolic and atherosclerotic risk factors were analyzed by multivariate regression models.

Results: Independent factors affecting CCA diameter were fat-free mass and waist girth (standardized r=0.44 and 0.12, p<0.01 and <0.0001, R²=0.35); independent correlates of IMT were age, CCA diameter, systolic BP and LDL-cholesterol (standardized r=0.39, 0.25, 0.10 and 0.14, p<0.005–0.0001, R²=0.40). MGL of carotid wall was independently associated with age and waist girth (standardized r=0.23 and 0.12, p<0.0001 and =0.001, R²=0.30).

Conclusions: Findings of this cross-sectional study suggest that BC modulates CCA diameter and may induce adaptive changes in carotid wall thickness, independently of metabolic and atherosclerotic factors. Central adiposity modifies the acoustic properties of carotid wall.