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DOI: 10.1055/s-2003-42691
Are Perinatal Risk Factors Helpful in Predicting and Optimizing Treatment Strategies for Transient Hypothyroxinemia in Very-Low-Birth-Weight Infants?
Publikationsverlauf
Publikationsdatum:
06. Oktober 2003 (online)
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ABSTRACT
Transient hypothyroxinemia is common in premature infants and has been associated with intraventricular hemorrhage (IVH), periventricular leukomalacia (PVL), poor neurodevelopmental outcomes, and mortality. Recent trials have failed to show that supplemental thyroid hormone improves overall neurodevelopmental outcome. The objective of this article is too determine perinatal risk factors for transient hypothyroxinemia (TH). We studied a cohort of infants born between July 1993 and July 2000 who were less than 1500 g and who received a newborn screening for thyroid function (n = 932). Total serum thyroxine (T4) was collected routinely on the fifth day of life. T4 was correlated with gestational age (R = 0.59, p < 0.01). After controlling for potential confounding variables, gestational age, dopamine, and mechanical ventilation were found to be independently associated with low T4 (overall model: r 2 = 0.41, p < 0.01). Number needed to treat (NNT) analysis showed treating all infants less than 27 weeks would lead to treating 6.3 infants for every one with a subsequent T4 < 5μg/dL. By combining gestational age and need for dopamine support, NNT = 2.4 for every one infant with subsequent T4 < 5μg/dL. Low gestational age, mechanical ventilation, and need for dopamine were associated with low T4 levels and may be helpful in optimizing treatment strategies for TH.
KEYWORDS
Thyroxine - transient hypothyroxinemia - prematurity
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