Increased Oxidative Stress in Prepubertal Children Born Small for Gestational Age

Abstract

Low birth weight is associated with an increased risk of metabolic and cardiovascular diseases in adulthood. The development of insulin resistance (IR) seems to play a pivotal role; no data on the oxidant-antioxidant status are available in this risk group. This study is an assessment of oxidant-antioxidant status in prepubertal children born small for gestational age (SGA) in comparison to healthy controls and the relationship to IR. This cross-sectional study compares indexes of IR and oxidant-antioxidant status in three different groups (SGA+, SGA-, controls), with analysis by post hoc and Pearson correlation. The study was conducted in the Academic Department of Pediatrics. A total of 19 SGA+ and 16 SGA- children were compared with 13 controls. No intervention was used. Indexes of IR (glucose to insulin ratio, homeostasis model assessment of IR) were evaluated, and markers of oxidative stress (lag phase, malonildialdehyde, vitamin E) were measured. Homeostasis model assessment of IR was significantly higher in SGA+ than SGA- children (1.32+/-0.9 vs. 0.69+/-0.47; P=0.03) and controls (0.71+/-0.37; P=0.04). Glucose to insulin ratio was significantly lower in SGA+ than SGA- children (12.41+/-5.01 vs. 26.54+/-17.18; P=0.02) and controls (26.96+/-20.70; P=0.04). Lag phase was significantly shorter in SGA+ than SGA- children (24.3+/-4.38 vs. 35.59+/-11.29 min; P=0.003) and controls (45.28+/-7.69 min; P=0.0001) and in SGA- than controls (P=0.01). Malonildialdehyde was significantly higher in SGA+ than SGA- children (0.79+/-0.3 vs. 0.6+/-0.1 nmol/mg; P=0.03) and controls (0.36+/-0.04 nmol/mg; P=0.0001) and in SGA- children than controls (P=0.02). Vitamin E was significantly reduced in SGA+ children than controls (27.54+/-7.9 vs. 43.23+/-11.32 micromol/liter; P=0.002). Oxidative stress is present in both SGA+ and SGA- children, with a continuous alteration in relation to IR. Therefore, catch-up growth might exert the greatest influence in the development of future diseases.