Vascular function and distribution of adiponectin isomers during puberty in children and adolescents with obesity.

INTRODUCTION Youth with obesity have abnormal vascular function that relates to the anti-atherogenic adipose-derived hormone, adiponectin. The distribution of adiponectin isomers changes during normal puberty, but there are no data in relation to vascular function. We aimed to evaluate vascular function, adiponectin, and its isomers longitudinally in peri-pubertal youth with obesity and controls. METHODS The study is a cohort longitudinal study involving 30 children and adolescents with obesity (body mass index [BMI] z-score 2.31 ± 0.24; age 12.8 ± 3 years, 17 male participants) and 28 age-/sex-matched healthy controls (12.8 ± 3 years, 14 male participants). Vascular function (flow-mediated dilatation [FMD], glyceryl trinitrate-mediated dilatation [GTN]), total adiponectin and isomers, and laboratory and clinical variables were assessed at 0, 18, and 36 months. RESULTS FMD and GTN were stable during puberty in both groups, remaining consistently lower in obese children (p = 0.02, p < 0.001). The change in total (p = 0.02) and high-molecular weight (HMW) (p = 0.02) adiponectin differed between the groups: falling in controls by the end of puberty but not falling further during puberty in obesity. In obesity, impaired GTN was associated longitudinally with lower total (B = 7.85, p = 0.006) and HMW (B = 3.72, p = 0.03) adiponectin. In controls, more favourable GTN was longitudinally associated with a lower BMI z-score (B = -3.04, p = 0.027) and lower waist circumference (B = -0.35, p = 0.009). CONCLUSIONS Vascular dysfunction and lower levels of adiponectin are associated in children and adolescents with obesity during puberty and do not deteriorate further. Healthy children's better vascular function, within the normal range, is associated with a lower BMI z-score and waist circumference.