Oral iodine supplementation in very low birth weight infants. Thyroid function and Neurodevelopmental follow up at 24 months. A Randomized Clinical Trial

Summary

This randomised controlled trial investigated whether oral iodine supplementation (30 µg/kg/day) in 47 very low birth weight infants (<1500 g) could improve thyroid function and neurodevelopmental outcomes compared to 47 unsupplemented controls. Supplemented infants reached recommended iodine intake from the first days of life, whilst control infants did not meet recommendations until 60 days of age; a positive relationship was observed between iodine intake and thyroid hormone concentrations in the first 60 days. The findings suggest thyroid function is iodine-intake dependent in preterm infants, with breast milk identified as the optimal iodine source.

Regional applicability

This Spanish study addresses a clinical issue relevant across high-income countries where preterm infant nutrition protocols vary. The findings on iodine requirements and breast milk composition are applicable to United Kingdom neonatal practice; however, UK infant formula fortification and standard care protocols may differ, and local thyroid screening programmes should be considered when interpreting recommendations for supplementation.

Key measures

Serum thyroid hormones (T4, free T4, T3, TSH), tyroglobulin, urinary iodine, breast milk iodine content, Bayley Scales of Infant Development at 24 months

Outcomes reported

The study measured thyroid hormone concentrations (T4, free T4, T3, TSH, tyroglobulin) and neurodevelopmental outcomes at 24 months (Bayley Test) in very low birth weight infants receiving oral iodine supplementation (30 µg/kg/day) versus control. Iodine content of breast milk and infant urine were also determined.

Topic tags