Does amount of protein in formula matter for low-birthweight infants? A Cochrane systematic review.

Abstract

BACKGROUND:

High protein intake may be associated with negative consequences such as acidosis, uremia, and elevated levels of circulating amino acids (eg, phenylalanine levels). We performed a systematic review of randomized controlled trials to determine whether formula-fed low-birthweight infants could tolerate protein intakes>or=3.0 g/kg/d in their initial hospital stay, without adverse consequences.

METHODS:

Randomized controlled trials contrasting levels of protein intakes as low (<3.0 g/kg/d), high (>or=3.0 g/kg/d but <4.0 g/kg/d), or very high protein intake (>or=4.0 g/kg/d) while other nutrients were held constant, were identified through a systematic search of the literature. Standard methods of the Cochrane Collaboration were used by 2 independent reviewers, with the third reviewer facilitating consensus decision making.

RESULTS:

A meta-analysis of 5 randomized trials indicated improved weight gain (weighted mean difference [WMD] 2.36 g/kg/d; 95% confidence interval [CI] 1.31-3.40) and higher nitrogen accretion (WMD 143.7 mg/kg/d; 95% CI 128.7-158.8) with high (>or=3.0 g/kg/d but <4.0 g/kg/d) compared with low (<3.0 g/kg/d) protein intakes while other nutrients were kept constant. No data were available for IQ or Bayley scores at 18 months or later or for very high protein intakes (>or=4.0 g/kg/d). No significant differences were seen in rates of necrotizing enterocolitis, sepsis, or diarrhea.

CONCLUSIONS:

Accelerated weight and nitrogen accretion were noted with higher protein intakes in "healthy" formula-fed low-birthweight infants. This benefit could not be weighed against the adverse consequences of elevated blood urea nitrogen levels and increased metabolic acidosis and neurodevelopmental abnormalities.

• Authors: Shahirose Premji, Tanis Fenton, Reg Sauve
• Journal: JPEN. Journal of parenteral and enteral nutrition (JPEN J Parenter Enteral Nutr) 2006 Nov-Dec Vol. 30 Issue 6 Pg. 507-14 ISSN: 0148-6071 [Print] United States
• PMID: 17047176 (Publication Type: Journal Article, Meta-Analysis, Research Support, Non-U.S. Gov't, Review, Systematic Review)

Chemical References

• Dietary Proteins
• Nitrogen

Topics

• Dietary Proteins (administration & dosage, adverse effects)
• Dose-Response Relationship, Drug
• Female
• Humans
• Infant
• Infant Nutritional Physiological Phenomena
• Infant, Low Birth Weight (growth & development)
• Infant, Newborn
• Intelligence (drug effects, physiology)
• Male
• Nervous System (drug effects)
• Nervous System Physiological Phenomena
• Nitrogen (metabolism)
• Randomized Controlled Trials as Topic
• Weight Gain (drug effects)