Relationship of adiposity with arterial stiffness as mediated by adiponectin in older men and women: the Hoorn Study

OBJECTIVE: To investigate whether adiponectin is associated with arterial stiffness, and whether adiponectin explains the association between body composition and arterial stiffness. DESIGN: Cross-sectional cohort study. METHODS: Subjects were participants (n=456, mean age 68.9+/-6.1 years; age range 60-86 years) of the third follow-up examination of the Hoorn Study. Trunk fat, leg fat, trunk lean, and leg lean mass were measured by dual-energy X-ray absorptiometry. Ultrasound was used to measure distensibility and compliance of the carotid, femoral, and brachial arteries, and carotid Young's elastic modulus (as estimates of peripheral arterial stiffness). Results Trunk fat mass was negatively associated with (ln-transformed) adiponectin (standardized beta=-0.49, P<0.001), while leg fat mass was positively associated with adiponectin (beta=0.44, P<0.001), after adjustment for each other, age, and lean mass. After adjustment for age, sex, mean arterial pressure, and estimated glomerular filtration rate, higher adiponectin was associated with decreased peripheral arterial stiffness (beta of mean Z-scores of all three arteries=0.14, P=0.001). However, the associations of trunk fat (beta=-0.26, P<0.001) and leg fat (beta=0.16, P=0.006) with peripheral arterial stiffness were only minimally explained by adiponectin levels. CONCLUSION: Trunk fat and leg fat are oppositely associated with adiponectin. Although low adiponectin was a determinant of increased peripheral arterial stiffness, it only explained a small part of the association between body fat and peripheral arterial stiffness. This indicated that factors other than adiponectin may be more important in the pathophysiological mechanisms by which abdominal obesity leads to arterial stiffness.