Serum adiponectin and leptin levels and insulin resistance in children born large for gestational age are affected by the degree of overweight

Abstract

Children born large for gestational age (LGA) are prone to develop insulin resistance later in life. One factor that affects insulin sensitivity is the hormone adiponectin. The aim of this study was to determine whether being LGA has an impact on serum adiponectin and leptin levels and insulin resistance parameters during childhood, taking into account the severity of overweight. Serum levels of adiponectin, leptin, fasting glucose and insulin, homeostasis model assessment insulin resistance index (HOMA-IR), and anthropometric indices were evaluated in groups of non-obese children aged 6.5-8 years, born appropriate for gestational age (AGA, n = 40) or LGA (n = 41), matched for age, gender, height, weight and body mass index. The LGA group was divided in two subgroups according to the degree of overweight: (a) LGA with birthweight 90th-97th percentile (n = 25); and (b) LGA with birthweight > 97th percentile (n = 16). LGA children had a higher mean serum adiponectin level than AGA children: 17.0 +/- 9 vs. 11.1 +/- 5 (microg/ml) (P < 0.01). LGA children had also higher insulin 6.2 +/- 2.8 vs. 4.8 +/- 2.4 (microU/ml) (P < 0.05) and HOMA-IR 1.32 +/- 0.66 vs. 1.02 +/- 0.55 (P < 0.01) than AGA children. Children born LGA > 97th percentile had a significantly higher mean serum leptin level than both AGA and LGA 90th-97th percentile children (17 +/- 13, 9.6 +/- 9.5, 7.8 +/- 7.9 ng/ml, respectively, P < 0.05), and more severely affected insulin resistance indices than LGA 90th-97th percentile children. In the regression analysis, birthweight was found to be an independent predictor of adiponectin serum levels. Prepubertal LGA-born children had a higher mean serum adiponectin levels than matched AGA controls despite the fact that they were more insulin resistant. The degree of excess in utero weight gain appears to influence the metabolic profile in LGA-born prepubertal children. Further studies are needed to delineate the role of adiponectin in the risk of development of insulin resistance in children born LGA.