Growth-restricted premature infants are at increased risk for low thyroxine. Academic Article uri icon

Overview

abstract

  • OBJECTIVE: To evaluate, in extremely premature infants, the relationship between growth restriction and early total thyroxine levels, and to determine how maternal, prenatal, perinatal and neonatal variables influence the relationship. STUDY DESIGN: 719 infants born at four medical centers in Massachusetts, New York and New Jersey between 1991 and 1993 were studied. Entry criteria included: gestational age 23--30 weeks, birth weight 500--1500 g, and a serum thyroxine level obtained in the first week of life. Infants born to mothers with a history of thyroid disease were excluded. Birth weight and total thyroxine level are expressed as z-scores (standard deviation units) to adjust for their relationship to gestational age. RESULTS: In linear regression analysis, there was a 0.18 decrease in the total thyroxine z-score for each 1.0 (1 standard deviation unit) decrease in birth weight z-score (p=0.0001). Adjustment for multiple potential maternal, prenatal, perinatal and neonatal confounders failed to identify a factor or factors that could account for the observed association. CONCLUSIONS: The early total thyroxine level in extremely preterm infants was significantly associated with birth weight z-score. This relationship persisted even after adjustment for maternal, prenatal, perinatal and neonatal confounders suggesting antenatal influences. Of clinical importance, growth-restricted infants are at increased risk for early hypothyroxinemia and, possibly, to its related morbidities.

publication date

  • September 1, 2001

Research

keywords

  • Fetal Growth Retardation
  • Infant, Premature
  • Infant, Very Low Birth Weight
  • Thyroxine

Identity

Scopus Document Identifier

  • 0034954321

Digital Object Identifier (DOI)

  • 10.1016/s0378-3782(01)00172-4

PubMed ID

  • 11440824

Additional Document Info

volume

  • 64

issue

  • 2