Gender differences in the relationships among obesity, adiponectin and brachial artery distensibility in adolescents and young adults

Background: Obesity-related cardiovascular diseases (CVDs) are a major cause of cardiovascular (CV) mortality. Obesity-related reduction in vascular protective adipose-derived proteins, such as adiponectin (APN), has an important role. Methods: We compared brachial artery distensibility (BrachD) with APN, the 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 whether APN provided an independent contribution to BrachD, while controlling for obesity and other CVRFs. Results: Male subjects had lower BrachD (5.72 +/- 1.37 vs 6.45 +/- 1.60% change per mmHg, P < 0.0001) and lower APN (10.50 +/- 4.65 vs 13.20 +/- 6.53; all P < 0.04) than female subjects. BrachD correlated with APN (r = 0.25, P < 0.0001). Both BrachD and APN correlated with measures of body size, including height, weight and body mass index (BMI). Both correlated with higher systolic blood pressure, glucose, insulin and lower high-density lipoprotein cholesterol ( all P < 0.01). In multivariate analysis, APN, gender, APN*gender and BMI z-score predicted BrachD (r(2) = 0.305). On the basis of gender difference, only BMI z-score was significant for male subjects (r(2) = 0.080), whereas APN and BMI z-score contributed for female subjects (r(2) = 0.242, all P < 0.0001). Conclusions: BrachD is independently influenced by obesity in both male and female subjects. In female subjects, APN exerts an additional independent effect even after adjusting for blood pressure ( BP), lipid levels and insulin. Differences in the effect of the APN-adiposity relationship on obesity-related vascular disease may be one reason for gender differences in the development and progression of atherosclerosis. International Journal of Obesity ( 2009) 33, 1118-1125; doi:10.1038/ijo.2009.164; published online 25 August 2009