Evaluation of DXA vs. MRI for body composition measures in 1-month olds

Pediatr Obes. 2015 Oct;10(5):e8-10. doi: 10.1111/ijpo.12021. Epub 2015 Mar 27.

Abstract

Background: Detailed measures of infant body composition are needed for understanding the impact of genes and environment on growth early in life.

Objective: The purpose of this study was to compare the accuracy and bias of body composition in infants.

Methods: Dual energy X-ray absorptiometry (DXA) and magnetic resonance imaging (MRI) were used to determine body composition and the trunk depot. The depots measured were total fat mass (FM), total fat-free mass (FFM) and trunk FM and FFM using DXA and MRI in 14 infants.

Results: None of the regression lines between DXA and MRI significantly deviate from the line of identity for any of the depots studied. However, Bland-Altman analyses revealed bias for trunk FM and trunk FFM.

Conclusion: Our data showed DXA to be accurate (regression not significantly deviating from the line of identity), with high agreement (indicated by high R(2) ) and without bias (non-significant Bland-Altman) when estimating total FM and FFM. This could not be said for trunk estimates.

Keywords: Body composition; fat mass; fat-free mass; growth; validation.

Publication types

  • Comparative Study
  • Evaluation Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Absorptiometry, Photon*
  • Adipose Tissue
  • Body Composition
  • Electric Impedance*
  • Female
  • Humans
  • Infant
  • Linear Models
  • Magnetic Resonance Imaging*
  • Male
  • Reproducibility of Results