Background: Strong association of early postnatal catchup growth in SGA with higher leptin levels and increased risk of insulin resistance has been described.
Objective: To determine leptin levels in term small for gestational age (SGA) children at 1518 months age and assess their relationship with postnatal catchup growth (CUG).
Methods: Birth and current weight and length of 60 term SGA (<10thpercentile) children at 1518 months was recorded and data analyzed for CUG (gain in weight/length SDS or both >0.67). Fasting leptin and insulin levels measured using ELISA kit and Electro-chemiluminescence, respectively. Insulin sensitivity evaluated using homeostatic model assessment index (HOMA-IR).
Results: Average birth weight, length, gestational age was 2.08±0.2 kg (−2.89±0.59 SD), 45.1±2.5 cm (−2.37±1.36 SD), 38.4±1.2 weeks respectively. At enrolment mean age, weight and length was 16.9±1.2 months, 8.2±0.8 kg (−2.00±0.98 SD), 73.0±3.0 cm (−2.36±1.11 SD). 39 (65%) of 60 SGA infants showed CUG and 21 did not have catchup growth (NCUG). Mean leptin levels were 2.3±1.8 ng/dl and higher in CUG (2.6±1.98 ng/dl) as compared to NCUG (1.8±1.20 ng/dl) but not statistically significant (P=0.09), however positively correlated with insulin levels, P=0.004 and HOMA-IR value, P=0.002. Insulin and HOMA-IR value significantly higher in CUG vs NCUG; 4.29±5.0 vs 2.15±1.9 μIU/ml, P=0.031 and 0.87 vs 0.43, P=0.039 respectively. Four children in CUG had HOMA-IR in insulin resistance range (HOMA-IR>2.0) with average leptin and insulin levels of 3.9 ng/ml and 17.6 μIU/ml respectively.
Conclusion: The rise in leptin levels was evident as early as 15 months in SGA children showing early postnatal catchup. Further, hyperinsulinemia and increased HOMA-IR value as marker of insulin resistance and adult metabolic syndrome were also observed. Therefore, high leptin levels strongly correlated with fasting insulin and HOMA-IR value in SGA with catchup growth indicating early onset of insulin resistance in these children.
20 - 22 Sep 2014
European Society for Paediatric Endocrinology