Insulin resistance and oxidative stress in children born small and large for gestational age.

Abstract

Our aim was to evaluate the effect of BW and obesity on oxidative stress and IR in prepubertal SGA and LGA children compared with appropriate-for-gestational-age (AGA) children. We performed a cross-sectional study comparing oxidative stress and IR in 103 children categorized into 6 groups according to BW (26 SGA, 15 AGA, and 16 LGA normal-weight children) and obesity (15 SGA, 15 AGA, and 16 LGA obese children). Indexes of IR (HOMA-IR, G/I) and the marker of oxidative stress (urinary isoprostanes) were evaluated. Homeostasis Model Assessment was higher in both normal-weight SGA and LGA children than in normal-weight AGA children (all P <or= .02). Furthermore, a difference was detected between obese SGA and obese LGA subjects compared with normal-weight SGA (all P <or= .0007) and LGA (all P <or= .01) children, respectively. The G/I ratio was lower in the 3 obese groups than normal-weight AGA (all P <or= .009) and normal-weight SGA children (all P <or= .02). Furthermore, a difference was detected between obese SGA and obese LGA children compared with normal-weight LGA children (all P <or= .0002). Isoprostane levels were higher in both normal-weight SGA and LGA children than in normal-weight AGA children (all P <or= .002). Moreover, both obese SGA and LGA children showed higher levels than obese AGA children (all P <or= .01) and in comparison to the 3 normal-weight groups (all P <or= .04). Increased IR and oxidative stress are already present in prepubertal normal-weight SGA and LGA children with a continuous alteration in relation to obesity, suggesting that BW and adiposity represent 2 independent risk factors for degenerative diseases.