Application of body mass index according to height-age in short and tall children

PLoS One. 2013 Aug 7;8(8):e72068. doi: 10.1371/journal.pone.0072068. eCollection 2013.

Abstract

Background: In children with either delayed or accelerated growth, expressing the body mass index (BMI) to chronological age might lead to invalid body composition estimates. Reference to height-age has been suggested for such populations; however its validity has not been demonstrated.

Methods: Anthropometric data of healthy children were obtained from the German KiGGS survey. We selected three samples with different height distributions representing short stature (mean height SDS: -1.6), normal stature (height SDS: 0), and tall stature (height SDS: +1.6), and compared BMI-for-age and BMI-for-height-age between these samples across the paediatric age range. Differences between samples were tested using Kruskal-Wallis one-way analysis of variance and permutation tests.

Results: At a given age, BMI was distributed towards lower values in short, and towards higher values in tall subjects as compared to a population with average height distribution. Expressing BMI to height-age eliminated these differences in boys with a short stature from 4 years to 14 years of age, in tall boys from 4 to 16 years, in short girls aged 2-10 years or tall girls aged 2-17 years.

Conclusion: From late infancy to adolescent age, BMI distribution co-varies with height distribution and referencing to height-age appears appropriate within this age period. However, caution is needed when data about pubertal status are absent.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Anthropometry / methods
  • Body Composition / physiology*
  • Body Height / physiology*
  • Body Mass Index*
  • Body Weight / physiology*
  • Child
  • Child, Preschool
  • Female
  • Humans
  • Male
  • Reproducibility of Results

Grant support

The ESPN/ERA-EDTA registry is funded by the European Renal Association and European Dialysis and Transplant Association (ERA-EDTA) and the European Society of Pediatric Nephrology (ESPN), and the European Agency for Health and Consumers of the European Commission (grant no. ESPNFY_2013). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.