Lower Serum Adiponectin Levels in African‐American Boys

Abstract Objective : To examine adiponectin, an adipocyte‐secreted hormone with anti‐inflammatory and insulin‐sensitizing effects, in relation to race or gender in younger subjects. Research Methods and Procedures : The relationship of adiponectin, quantitated by radioimmunoassay, to anthropometric and metabolic factors (fasting insulin, glucose, and leptin) and reproductive hormones was examined in 46 healthy African Americans (25 girls/21 boys) and 40 whites (20 girls/20 boys) ranging in age from 12 to 21 years. Results : There was no statistical difference in BMI or in BMI percentile among the four groups. Sums of skinfolds, but not skinfold percentile, were significantly lower in boys than girls ( p = 0.001 and p = 0.896, respectively), whereas there was no difference between racial groups. Leptin was significantly greater in girls ( p = 0.0002). There was no difference in fasting serum glucose, insulin, or homeostasis model assessment score among any of the groups. There was a significant negative univariate relationship between serum adiponectin and both BMI and BMI percentile for the entire group ( p = 0.006 and p = 0.005). In a multivariate model, BMI percentile ( p = 0.005) and the interaction between race and gender ( p = 0.026) were significant predictors of serum adiponectin. In this model, African‐American boys had the lowest serum adiponectin level, 37% less than white boys, who had the highest adiponectin levels. Discussion : Serum adiponectin levels are reduced in young obese subjects (African Americans and whites) and are lower in African‐American boys than white boys. A lower adiponectin level in African‐American boys may predispose this group to a greater risk of diabetes and cardiovascular disease.