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Highest Plasma Phenylalanine Levels in (Very) Premature Infants on Intravenous Feeding; A Need for Concern
Ernesto Cortés-Castell1, Pablo Sánchez-González2, Antonio Palazón-Bru3
1Department of Pharmacology, Paediatrics and Organic Chemistry, Miguel Hernández University, San Juan de Alicante, Spain.
Insights
Newborn blood phenylalanine levels are higher in premature infants and those on intravenous feeding. Careful monitoring and tailored nutrition are crucial for these vulnerable newborns.
Area of Science:
- Neonatal Medicine
- Biochemistry
- Pediatrics
Background:
- Blood phenylalanine levels are a key indicator in newborn screening.
- Gestational age and feeding methods can influence neonatal metabolic profiles.
Purpose of the Study:
- To investigate the relationship between blood phenylalanine levels and feeding methods in newborns.
- To examine the association between phenylalanine levels and gestational age in neonates.
Main Methods:
- An observational, cross-sectional study of 11,829 infants (2008-2013) in Spain.
- Data collected on phenylalanine values, feeding method (breast, formula, mixed, intravenous), and gestational age.
- Multivariate linear and logistic regression models were used for analysis.
Main Results:
- Higher phenylalanine concentrations were significantly associated with lower gestational age (p<0.001).
- Intravenous feeding was also strongly correlated with elevated phenylalanine levels (p<0.001).
Conclusions:
- Prematurity and intravenous nutrition significantly impact newborn plasma phenylalanine concentrations.
- Close monitoring of phenylalanine levels is recommended for infants receiving intravenous feeding.
- Adjusting nutrient intake based on individual infant needs is essential, particularly for very preterm infants.
Objective:
To analyse the association in newborns between blood levels of phenylalanine and feeding method and gestational age.
Study Design:
This observational, cross-sectional study included a sample of 11,829 infants between 2008 and 2013 in a Spanish region. Data were recorded on phenylalanine values, feeding method [breast, formula, mixed (breast plus formula), or partial or fully intravenous feeding], gestational age in weeks (<32, 32-37, ≥37), gender and days since birth at the moment of blood collection. Outcomes were [phenylalanine] and [phenylalanine] ≥95th percentile. Associations were analysed using multivariate models [linear (means difference) and logistic regression (adjusted odds ratios)].
Results:
Higher phenylalanine values were associated with lower gestational age (p<0.001) and with intravenous feeding (p<0.001).
Conclusion:
The degree of prematurity and intravenous feeding influenced the plasma concentration of phenylalanine in the newborn. Caution should be taken in [phenylalanine] for newborns with intravenous feeding, monitoring them carefully. Very preterm infants given the recommended amount of amino acids should also be strictly monitored. These findings should be taken into consideration and call for adapting the amounts to the needs of the infant.
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