Neonatal cord blood adiponectin and insulin levels in very low birth weight preterm and healthy full-term infants

Abstract

Background: There are few studies concerning adiponectin and insulin concentration in cord blood of very low birth weight (VLBW) preterm and full-term newborns, small and appropriate for gestational age (GA).

Aim: To compare adiponectin and insulin concentrations between preterm and full-term infants, and to determine their relation with birth weight (BW) and size for GA.

Methods: A cross-sectional study of VLBW preterm newborns with GA < 32 weeks and BW < 1500 g, and full-term newborns with GA > 37 weeks born at our hospital between January 2010 and May 2011, was conducted. Exclusion criteria: major congenital malformation, inborn errors of metabolism, chromosomal anomalies. Adiponectin was determined by enzimoimunoassay with ELISA kits (R&D Systems, Minneapolis, MN) and insulin was assayed by chemiluminescence method.

Results: A total of 127 newborns were studied, 55 VLBW preterm (28 SGA), and 72 full-term (7 SGA). Insulin cord blood concentrations in preterm and full-term newborns were similar. Adiponectin concentrations were significantly lower in preterm than in full-term infants: 1.57 ± 0.74 pg/ml versus 2.4 ± 0.22 pg/ml (p < 0.001), respectively. Regression analyses showed that, after controlling for several neonatal and maternal factors, preterm birth was the only significant predictor of adiponectin concentrations.

Conclusion: Being born prematurely is the main determinant factor for lower adiponectin concentration in umbilical cord blood of newborns.

• Adiponectin
• newborn
• preterm
• very low birth weight

Acknowledgements

The authors would like to thank Vania Naomi Hirakata (Statistical Consulting) for her help with statistical analyses; the patients and families for participating in the protocol; Dr Úrsula Matte and Larissa Lutz for laboratory assistance and Linda Booij for the English revision.

The authors’ responsibilities were as follows - ACT: study design, data collection and analysis, and manuscript writing; RSP: study design, counseling, supervision, manuscript writing; RCS: study design, supervision, manuscript writing, coordinator of the study; all authors read and approved the final manuscript.