Background Few studies have presented data on adiponectin and leptin levels comparing small and appropriate for gestational age, and very low birth weight preterm and term newborns.
Aim To compare levels of adiponectin and leptin in cord blood of full term and very low birth weight preterm infants, and determine its relation with birth weight and being small for gestational age.
Methods Cross sectional study of preterm with gestational age (GA) ≤32 weeks and birth weight ≤1500 grams (VLBW), and term newborns born at tertiary hospital between January 2010 and May 2011. Exclusion criteria were presence of major congenital malformation, metabolism inborn errors, chromosomal anomalies. Adiponectin and leptin cord blood levels were determined by ELISA kits (R&D Systems).
Results Included 127 newborns: 55 VLBW preterm and 72 term newborns. There were no statistical differences regarding maternal gestational diabetes, urinary tract infection, age and BMI. Adiponectin levels were significantly higher in term than in preterm newborns: 2.4±0.22pg/ml versus 1.57±0.74 pg/ml (p<0.001), respectively; leptin levels were similar in both groups: 1.25 ±0.90pg/ml and 1.38 ±0.99pg/ml (p=0.481), respectively. Despite being adequate or small for gestational age, VLBW preterm newborns showed lower levels of adiponectin than term newborns (p<0.001), and there were no statistically significant differences for leptin levels. In the linear regression, prematurity was the only independent variable associated to low levels of adiponectin (p<0.001).
Conclusion Prematurity is the main determinant factor for lower adiponectin levels in umbilical cord blood of newborns.