De Onis 2007 Bull World Health Organization

de Onis M, Onyango AW, Borghi E, Siyam A, Nishida C, Siekmann J (2007) Development of a WHO growth reference for school-aged children and adolescents. Bull World Health Organization 85:660-7.

» PMID: 18026621 Open Access

de Onis M, Onyango AW, Borghi E, Siyam A, Nishida C, Siekmann J (2007) Bull World Health Organization

Abstract: OBJECTIVE: To construct growth curves for school-aged children and adolescents that accord with the WHO Child Growth Standards for preschool children and the body mass index (BMI) cut-offs for adults.

METHODS: Data from the 1977 National Center for Health Statistics (NCHS)/WHO growth reference (1-24 years) were merged with data from the under-fives growth standards' cross-sectional sample (18-71 months) to smooth the transition between the two samples. State-of-the-art statistical methods used to construct the WHO Child Growth Standards (0-5 years), i.e. the Box-Cox power exponential (BCPE) method with appropriate diagnostic tools for the selection of best models, were applied to this combined sample.

FINDINGS: The merged data sets resulted in a smooth transition at 5 years for height-for-age, weight-for-age and BMI-for-age. For BMI-for-age across all centiles the magnitude of the difference between the two curves at age 5 years is mostly 0.0 kg/m(2) to 0.1 kg/m(2). At 19 years, the new BMI values at +1 standard deviation (SD) are 25.4 kg/m(2) for boys and 25.0 kg/m(2) for girls. These values are equivalent to the overweight cut-off for adults (> or = 25.0 kg/m(2)). Similarly, the +2 SD value (29.7 kg/m(2) for both sexes) compares closely with the cut-off for obesity (> or = 30.0 kg/m(2)).

CONCLUSION: The new curves are closely aligned with the WHO Child Growth Standards at 5 years, and the recommended adult cut-offs for overweight and obesity at 19 years. They fill the gap in growth curves and provide an appropriate reference for the 5 to 19 years age group.

• Bioblast editor: Gnaiger E

From BMI to BME

Contributed by Gnaiger E (last update: 2020-01-19)

Figure 1: Growth curves and allometry of body mass and height in girls and boys from 5 to 19 years (WHO 2006). (a) and (b): Height and body mass as a function of age. The curves are very similar up to 13 years. (c) and (d) Body mass and precision body mass index, BMI°, as a function of height. Three allometric phases are indicated by the shaded areas. The BMI does not yield an index that is independent of height.

Figure 1 is based on the WHO Child Growth Standards [1-3]. It illustrates the limitation of the BMI as an index of overweight and obesity. The precision body mass index, BMI°, is claculated for the healthy reference population (HRP), in which neither underweight nor overweight prevails and which, therefore, should be characterized by a constant index. This is achieved by the body mass excess, BME [4], which relates the actual body mass, M, to the reference body mass, M°, at a given height, BME=(M-M°/M°). The BME is constant at 0.0 for the HRP for both sexes independent of height. In contrast, the increase of the precision BMI° from 15 to 21 kg·m^-2 from 1.0 to 1.8 m represents a confounding factor which explains the necessity of adjusting the BMI cutoff points. Instead of a focus on adjusted BMI cutoff points [3], research should focus on evaluation of the concept of BME and the HRP.

References

1. WHO Multicentre Growth Reference Study Group (2006) WHO child growth standards based on length/height, weight and age. Acta Pædiatrica Suppl 450:76-85.
2. WHO Multicentre Growth Reference Study Group (2006) WHO child growth standards: length/height-for-age, weight-for-age, weight-for-length, weight-for-height and body mass index-for-age: Methods and development. Geneva: World Health Organization:312 pp.
3. de Onis M, Onyango AW, Borghi E, Siyam A, Nishida C, Siekmann J (2007) Development of a WHO growth reference for school-aged children and adolescents. Bull World Health Organization 85:660-7.
4. Healthy reference population
5. Body mass excess

Labels: MiParea: Gender, Developmental biology  Pathology: Obesity 

Organism: Human 

Preparation: Intact organism 

BMI, BME