Nitrogen utilization and bone mineralization in very low birth weight infants fed partially hydrolyzed preterm formula.
Partialy hydrolyzed formulas have been proposed for term and preterm infants, but decreased nitrogen and calcium intestinal absorption rates, together with plasma amino acid imbalances have been reported in preterm infants. We evaluated a new formula with modified nitrogen and calcium sources (glycerophosphate). During their second week of life, 16 preterm infants were randomly assigned to 1 of 2 groups: 9 were fed the new partially hydrolyzed formula and 7 a conventional formula. A nutrient balance was performed at the end of the first month of life. Amino acid concentrations and whole-body mineralization were measured at the end of study period (theoretical term). Birth weight and gestational age (mean +/- SD) were similar in the 2 groups (28.9 +/- 7.0 wks and 1,183 +/- 242 g v 27.7 +/- 1.0 wks and 1,139 +/- 162 g). Median nitrogen absorption rate (85% v 89%; P = .03) was lower in infants fed the new formula than in those fed the conventional one. After correction for difference in nitrogen intake, there was no significant difference in N retained between the 2 groups (P = .11). Plasma amino acid concentrations were also similar in the 2 groups. At theoretical term, median bone mineral content was not significantly different between the 2 groups (50 g/kg v 55 g/kg; P = .17) and it was close to the reference values obtained in term neonates just after birth. As long as nitrogen content is 10% higher in protein hydrolyzed formula than in entire protein formula, appropriate nitrogen retention, plasma amino acid profile can be achieved with the new partially hydrolyzed formula. In both groups, bone mineralization at theoretical term was close to the mineralization observed term neonates just after birth.
Picaud
Jean-Charles
JC
Neonatology and Human Nutrition Research Center, Edouard Herriot Hospital, Claude Bernard University, Lyon, France. jc-picaud@chu-montpellier.fr
Lapillonne
Alexandre
A
Rigo
Jacques
J
Normand
Sylvie
S
Reygrobellet
Bernadette
B
Claris
Olivier
O
Salle
Bernard L
BL
D000596:Amino Acids / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism; D001835:Body Weight; D002113:Calcification, Physiologic / Q000502:physiology*; D005260:Female; D006801:Humans; D007225:Infant Food; D007227:Infant Nutritional Physiological Phenomena / Q000502:physiology*; D007231:Infant, Newborn; D007234:Infant, Premature / Q000254:growth & development / Q000378:metabolism*; D019102:Infant, Very Low Birth Weight / Q000254:growth & development / Q000378:metabolism*; D008297:Male; D009584:Nitrogen / Q000378:metabolism*; D011492:Protein Hydrolysates / Q000378:metabolism
D000596:Amino Acids; D011492:Protein Hydrolysates; D009584:Nitrogen