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Determining Basal Energy Expenditure and the Capacity of Thermogenic Adipocytes to Expend Energy in Obese Mice
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Total energy expenditure, body composition and weight gain in moderately preterm and full-term infants at term

E Olhager1, E Forsum

  • 1Department of Molecular and Clinical Medicine, Division of Paediatrics, University of Linköping, University Hospital, Linköping, Sweden. elisabeth.olhager@lio.se

Acta Paediatrica (Oslo, Norway : 1992)
|December 31, 2003
PubMed

Insights

Healthy preterm infants at term postconceptional age had higher total energy expenditure (TEE) and catch-up growth compared to full-term newborns, despite being smaller with similar body fat. This suggests higher growth rates and physical activity in preterm infants.

Area of Science:

  • Neonatal physiology and metabolism.
  • Pediatric growth and development.

Background:

  • Preterm infants born between 30-33 weeks gestation face unique metabolic and growth challenges.
  • Understanding body composition and energy expenditure is crucial for optimizing care in preterm neonates.

Purpose of the Study:

  • To compare total energy expenditure (TEE), total body water (TBW), and adipose tissue volume (ATV) at term-equivalent age in healthy preterm and full-term infants.
  • To investigate body composition differences and growth patterns between these groups.

Main Methods:

  • Magnetic resonance imaging (MRI) for assessing total and subcutaneous adipose tissue volumes (ATV).
  • Doubly labeled water (DLW) method for estimating total energy expenditure (TEE) and total body water (TBW).

Main Results:

  • Preterm infants exhibited significantly higher TEE (315 kJ/kg/24h) compared to full-term infants (254 kJ/kg/24h).
  • Both groups showed similar proportions of total body water (TBW) and adipose tissue (ATV) relative to body weight.
  • Preterm infants weighed less but demonstrated a higher weight gain rate (38 g/24h) compared to full-term infants (24 g/24h).

Conclusions:

  • Healthy preterm infants at term postconceptional age are smaller but exhibit catch-up growth with similar body fat proportions to full-term infants.
  • Higher TEE per kilogram in preterm infants is likely attributed to accelerated growth rates and potentially increased physical activity.
  • These findings highlight distinct metabolic adaptations in preterm infants requiring tailored nutritional and developmental support.
Abstract

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