Visfatin in juvenile obesity - the effect of obesity intervention and sex

Background The association of visfatin, an adipocytokine relevant to the development of inflammation and metabolic disorders, with juvenile obesity needs to be re-established as previously used tests occurred to be nonspecific. Objective To evaluate visfatin association with a metabolic profile of 88 overweight / obese and 26 lean children / adolescents as well as changes in its levels following weight reduction programme (diet + enhanced physical activity +/- metformin). Design A case-control and cohort study. Results Visfatin was higher in obese than lean and overweight individuals (2 07 vs. 1 53 and 1 47 ng mL) 1, P = 0 034). Of metabolic syndrome components, central obesity combined with either insulin resistance (IR) or hyperinsulinemia (HI) was associated with increases in circulating visfatin. In girls, visfatin correlated with leptin (r = 0 40, P = 0 009) and thiols (r =) 0 36, P = 0 009), which explained 24% in visfatin variability. In boys, visfatin correlated with waist circumference (r = 0 36, P = 0 036), BMI% (r = 0 38, P = 0 025), whole body insulin sensitivity index (r =) 0 36, P = 0 036), IL-6 (r = 0 38, P = 0 024) and thiobarbituric acid reactive substances (TBARS) (r = 0 52, P = 0 001), of which IL-6 and TBARS were independent predictors of visfatin elevation, explaining 42% in data variability. Visfatin was significantly lower following weight reduction programme than at baseline (1 43 vs. 1 83 ng mL) 1, P = 0 033). Visfatin reduction correlated neither with changes in metabolic parameters nor was it affected by metformin. DVisfatin correlated exclusively with baseline visfatin (r = 0 612, P < 0 0001), which explained 38% in data variability. Conclusions Central obesity combined with HI / IR contributes to visfatin elevation. Visfatin association with metabolic / biochemical variables is gender dependent. Diet + enhanced physical activity are effective in visfatin reduction, the degree of which depends on baseline visfatin.