Neurodevelopmental evaluation of very low birth weight infants with transient hypothyroxinemia at corrected age of 18-24 months.

OBJECTIVE: To perform neurodevelopmental evaluation at 18 to 24 months corrected age in very low birth infants (VLBW) with transient hypothyroxinemia.

DESIGN: Cohort study.

SETTING: Maternity teaching hospital.

PATIENTS: Premature infants who were previously evaluated for thyroid hormone values in the first weeks of life were included.

INTERVENTION: Data of these infants who weighed <1500 g and <32 weeks of gestation were retrieved for the current study. Available subjects (n=56) were evaluated for neurodevelopmental status at 18 to 24 months of corrected age. Bayley Scales of Infant Development Second Edition (BSID II) was performed to define Mental developmental index (MDI) and Psychomotor developmental index (PDI).

RESULTS: The mean MDI and PDI scores were similar between the infants with and without transient hypothyroxinemia of prematurity (THOP) [79.9 ± 14.9 vs 70 ± 20.7, respectively (P=0.54); and 92.2 ± 16.4 vs 85.6 ± 18.9, respectively (P=0.68)]. After adjustment for gestational age and multiple prenatal, perinatal, and early and late neonatal variables, THOP was not associated with an increased risk of disabling cerebral palsy, or a reduction of MDI and PDI scores.

CONCLUSIONS: THOP may not be an important cause of problems in neurologic and mental development detected at the age of 18 to 24 months corrected age.