Vitamin A status of preterm infants: correlation between plasma retinol concentration and retinol dose response

Area of Science:

• Neonatal Nutrition
• Vitamin A Metabolism
• Pediatric Endocrinology

Background:

• Vitamin A is crucial for infant development and immune function.
• Preterm infants are at risk for vitamin A deficiency due to limited stores and altered metabolism.
• Assessing vitamin A status in preterm neonates is essential for appropriate supplementation.

Purpose of the Study:

• To evaluate the dose-response relationship of oral vitamin A (retinol) supplementation in preterm infants.
• To investigate the impact of a single retinol dose on plasma retinol and related protein levels before hospital discharge.
• To infer the hepatic vitamin A stores in preterm infants based on their response to supplementation.

Main Methods:

• Administered a 5000 IU oral dose of an aqueous retinol dispersion to 83 preterm infants.
• Measured predose plasma retinol concentrations.
• Assessed the dose response of plasma retinol and monitored levels of retinol-binding protein, prealbumin, and their ratios.

Main Results:

• Predose plasma retinol ranged from 2.5-20.5 µg/dL.
• The observed retinol dose response varied widely (0-59.8%).
• A negative regression (-0.58) of dose response on predose retinol was observed, alongside increased retinol-binding protein and a higher retinol-binding protein to prealbumin ratio, without prealbumin increase.

Conclusions:

• Preterm infants exhibit a blunted or variable response to a single oral retinol dose.
• The findings suggest that preterm infants may possess diminished hepatic stores of vitamin A.
• Further research into optimal vitamin A supplementation strategies for preterm neonates is warranted.