Gender Differences in the Relationships Among Obesity, Adiponectin and Brachial Artery Distensibility in Adolescents and Young Adults

BACKGROUND: Obesity-related CV diseases are a major cause of CV mortality. Obesity-related reduction in vascular protective adipose-derived proteins like adiponectin (APN) play a role. METHODS: We compared brachial artery distensibility (BrachD) to APN, level of adiposity and other CV risk factors (CVRFs) in 431 post-pubertal subjects (mean 17.9 years). Gender differences in average values were examined by t-tests. Correlations among BrachD, obesity and other CVRFs were examined. Regression analysis was performed to determine if APN provided independent contribution to BrachD, controlling for obesity and other CVRFs. RESULTS: Males had lower BrachD than females (5.72 + 1.37 vs 6.45 + 1.60 %change/mmHg, p < 0.0001) and lower APN (10.50 + 4.65 vs 13.20 + 6.53), (all p < 0.04). BrachD correlated with APN (r = 0.25, p< 0.0001). Both BrachD and APN correlated with measures of body size including height, weight, and BMI. Both correlated with higher SBP, glucose, insulin, and lower HDL-C (all p <0.01). In multivariate analysis, APN, gender, APN*gender and BMI z-score predicted BrachD (r(2) = 0.305). By gender, only BMI z-score was significant for males (r(2) = 0.080). For females APN and BMI z-score contributed (r(2) = 0.242, all p<0.0001). CONCLUSIONS: BrachD is independently influenced by obesity in both males and females. In females, APN exerts an additional independent effect even after adjusting for BP, lipid levels and insulin. Differences in the effect of the APN — adiposity relationship on obesity-related vascular disease may be one mechanism for gender differences in the development and progression of atherosclerosis.