Targeting 2.5 versus 4 g/kg/day of amino acids for extremely low birth weight infants: a randomized clinical trial

Area of Science:

• Neonatal Nutrition
• Pediatric Metabolism
• Infant Neurodevelopment

Background:

• Parenteral nutrition (PN) is crucial for extremely low birth weight (ELBW) infants.
• Optimizing amino acid (AA) delivery is essential for metabolic tolerance, growth, and neurodevelopment.
• The optimal AA dosage in PN for ELBW infants remains under investigation.

Purpose of the Study:

• To compare the effects of standard (2.5 g/kg/d) vs. high (4 g/kg/d) amino acid (AA) intake via parenteral nutrition (PN) in ELBW infants.
• To assess the impact on metabolic tolerance, short-term growth, and neurodevelopmental outcomes.
• To determine if increased AA provision improves outcomes in ELBW infants.

Main Methods:

• Randomized controlled trial involving 131 ELBW infants (500-1249 g birth weight).
• Infants were assigned to receive either 2.5 g/kg/d (standard AA [SAA] group) or 4 g/kg/d (high AA [HAA] group) of AA, with equal nonprotein energy.
• Primary outcome was body size at 36 weeks; neurodevelopment assessed using Bayley Scales of Infant and Toddler Development, Third Edition.

Main Results:

• Higher blood urea levels (24% vs. 59%) and better glucose control (34% vs. 11%) were observed in the SAA and HAA groups, respectively.
• No significant differences in body weight, length, or head circumference at 36 weeks and 2 years between groups.
• Neurodevelopmental scores (Bayley III) were similar between the SAA (94 ± 13) and HAA (97 ± 15) groups.

Conclusions:

• High AA intake improved metabolic tolerance, indicated by higher blood urea and better glucose control.
• Increased AA provision (an additional 8 g/kg over 10 days) did not lead to improved growth or neurodevelopmental outcomes in ELBW infants.
• Current AA dosing strategies may need re-evaluation for optimal ELBW infant outcomes.