Glucose and lipid metabolism in small for gestational age infants at 48 hours of age.
OBJECTIVE
To study the consequences of low birth weight on glucose and lipid metabolism 48 hours after delivery.


METHODS
We studied 136 small for gestational age (SGA) and 34 appropriate for gestational age (AGA) term neonates who were born in Santiago, Chile. Prefeeding venous blood was obtained 48 hours after birth for determination of glucose, free fatty acids, beta-hydroxy butyrate, insulin, C-peptide, leptin, sex hormone-binding globulin, insulin-like growth factor-binding protein-1 (IGFBP-1), and cortisol.


RESULTS
SGA newborns had lower glucose (SGA versus AGA, median [interquartile range]: 3.6 mmol/L [2.9-4.1 mmol/L] vs 3.9 mmol/L [3.6-4.6 mmol/L]) and insulin levels (31.3 pmol/L [20.8-47.9 pmol/L] vs 62.5 pmol/L [53.5-154.9]) than AGA infants, and they had higher glucose/insulin ratios (13.9 mg/dL/uIU/mL [8.6-19.1 mg/dL/uIU/mL] vs 8.2 mg/dL/uIU/mL [4.6-14.1 mg/dL/uIU/mL]). SGA infants also had higher levels of IGFBP-1 (5.1 nmol/L [4.4-6.7 nmol/L] vs 2.9 nmol/l [1.4-4.2 nmol/L]), free fatty acids (0.72 mEq/L [0.43-1.00 mEq/L] vs 0.33 mEq/L [0.26-0.54 mEq/L]) and beta-hydroxy butyrate (0.41 mEq/L [0.15-0.91 mEq/L] vs 0.09 mEq/L [0.05-0.13 mEq/L]). Sex-hormone binding globulin levels were not significantly different between the 2 groups.


CONCLUSIONS
In early postnatal life, SGA infants display an increased insulin sensitivity with respect to glucose disposal but not with respect to suppression of lipolysis, ketogenesis, and hepatic production of IGFBP-1. It will be important to determine how these differential sensitivities to insulin vary with increasing age.
Bazaes
Rodrigo A
RA
Institute for Maternal and Child Research, School of Medicine, University of Chile, Santiago, Chile.
Salazar
Teresa E
TE
Pittaluga
Enrica
E
Peña
Verónica
V
Alegría
Angélica
A
Iñiguez
Germán
G
Ong
Ken K
KK
Dunger
David B
DB
Mericq
M Verónica
MV
D020155:3-Hydroxybutyric Acid / Q000097:blood; D001786:Blood Glucose; D002096:C-Peptide / Q000378:metabolism; D005260:Female; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age / Q000097:blood / Q000378:metabolism*; D007328:Insulin / Q000097:blood; D018970:Insulin-Like Growth Factor Binding Protein 1 / Q000097:blood; D020738:Leptin / Q000097:blood; D050356:Lipid Metabolism; D008055:Lipids / Q000097:blood; D008297:Male; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism
D001786:Blood Glucose; D002096:C-Peptide; D007328:Insulin; D018970:Insulin-Like Growth Factor Binding Protein 1; D020738:Leptin; D008055:Lipids; D012738:Sex Hormone-Binding Globulin; D005947:Glucose; D020155:3-Hydroxybutyric Acid; D006854:Hydrocortisone