Altered brain metabolite concentration and delayed neurodevelopment in preterm neonates

Area of Science:

• Neonatal neuroscience
• Developmental pediatrics
• Magnetic resonance spectroscopy (MRS)

Background:

• Very-low-birth-weight (VLBW) preterm infants face heightened risks of impaired neurodevelopmental outcomes.
• Understanding brain metabolite changes in relation to postmenstrual age is crucial for predicting long-term development.
• This study investigates the dynamic changes in neonatal brain metabolites and their correlation with neurodevelopmental trajectories.

Purpose of the Study:

• To examine how neonatal brain metabolite concentrations evolve with postmenstrual age in VLBW preterm infants.
• To determine the relationship between the rate of change (slopes) in brain metabolite concentrations and neurodevelopmental levels at 3-4 years of age.
• To identify specific metabolites whose concentration changes are predictive of neurodevelopmental outcomes.

Main Methods:

• Retrospective analysis of 108 VLBW preterm infants using brain single-voxel magnetic resonance spectroscopy (MRS) at 34-42 weeks' postmenstrual age.
• Neurodevelopmental assessment at 3-4 years using a standardized developmental test, classifying infants into four groups based on developmental quotient (DQ).
• Statistical comparison of metabolite concentration slopes across developmental groups using ANCOVA and post hoc tests.

Main Results:

• Significant correlations were observed between postmenstrual age and concentrations of tNAA, creatine/phosphocreatine, glutamate/glutamine, and myo-inositol in deep gray matter.
• tNAA concentrations in the centrum semiovale also correlated significantly with postmenstrual age.
• A significant interaction was found for tNAA slopes in the deep gray matter, with a notable difference between the lowest (<70) and higher (85-100) DQ groups.

Conclusions:

• The rate of change in N-acetylaspartate and N-acetylaspartylglutamate (tNAA) concentrations, adjusted for postmenstrual age, is associated with neurodevelopmental outcomes in VLBW preterm infants.
• A slower increase in tNAA brain concentration at term-equivalent age predicts poorer developmental outcomes at 3-4 years.
• Changes in tNAA concentration appear more critical than changes in total choline (tCho) for predicting developmental delays in this population.