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Difference between revisions of "Cole 2000 BMJ"

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== From BMI to BME ==
  Contributed by [[Gnaiger E]] (last update: 2020-01-19)
  Contributed by [[Gnaiger E]] (last update: 2020-01-19)
== From BMI to BME ==
 
[[File:BMI-cutoff age.png|left|600px|thumb|'''Figure 1''': BMI cutoff values as a function of age. The symbols are from Table 4 of Cole et al (2010), compared to the personalized BMI cutoff points derived from the concept of body mass excess, BME. BMI<sub>0.2</sub> and BMI<sub>0.4</sub> are the personalized BMI cutoff points for overweight and obese, calculated from the reference body mass, ''M''° of the HRP, and the body mass thresholds as a function of height, 1.2''M''° and 1.4''M''°.]]
[[File:BMI-cutoff age.png|left|600px|thumb|'''Figure 1''': BMI cutoff values as a function of age. The symbols are from Table 4 of Cole et al (2010), compared to the personalized BMI cutoff points derived from the concept of body mass excess, BME. BMI<sub>0.2</sub> and BMI<sub>0.4</sub> are the personalized BMI cutoff points for overweight and obese, calculated from the reference body mass, ''M''° of the HRP, and the body mass thresholds as a function of height, 1.2''M''° and 1.4''M''°.]]



Revision as of 19:27, 19 January 2020

Publications in the MiPMap
Cole TJ, Bellizzi MC, Flegal KM, Dietz WH (2000) Establishing a standard definition for child overweight and obesity worldwide: international survey. BMJ 320:1240-3.

» PMID: 10797032 Open Access

Cole TJ, Bellizzi MC, Flegal KM, Dietz WH (2000) BMJ

Abstract: OBJECTIVE: To develop an internationally acceptable definition of child overweight and obesity, specifying the measurement, the reference population, and the age and sex specific cut off points.

DESIGN: International survey of six large nationally representative cross sectional growth studies.

SETTING: Brazil, Great Britain, Hong Kong, the Netherlands, Singapore, and the United States.

SUBJECTS: 97 876 males and 94 851 females from birth to 25 years of age.

MAIN OUTCOME MEASURE: Body mass index (weight/height(2)).

RESULTS: For each of the surveys, centile curves were drawn that at age 18 years passed through the widely used cut off points of 25 and 30 kg/m(2) for adult overweight and obesity. The resulting curves were averaged to provide age and sex specific cut off points from 2-18 years.

CONCLUSIONS: The proposed cut off points, which are less arbitrary and more internationally based than current alternatives, should help to provide internationally comparable prevalence rates of overweight and obesity in children.

PIP: This study aimed to develop an internationally acceptable definition of child overweight and obesity, specifying the measurement, reference population, and age and sex specific cut off points. Data on body mass index (weight/height) were obtained from 6 large nationally representative cross sectional surveys on growth from Brazil, Great Britain, Hong Kong, the Netherlands, Singapore, and the US. The study included 97,876 males and 94,851 females from birth to 25 years of age. For each of the surveys, centile curves were drawn that at age 18 years passed through the widely used cutoff points of 25 and 30 kg/sq. m for adult weight and obesity. The resulting curves were averaged to provide age- and sex-specific cutoff points from 2 to 18 years. The proposed cut off points, which are less arbitrary and more internationally based than current alternatives, should help to provide internationally comparable prevalence rates of overweight and obesity in children.

Bioblast editor: Gnaiger E

From BMI to BME

Contributed by Gnaiger E (last update: 2020-01-19)
Figure 1: BMI cutoff values as a function of age. The symbols are from Table 4 of Cole et al (2010), compared to the personalized BMI cutoff points derived from the concept of body mass excess, BME. BMI0.2 and BMI0.4 are the personalized BMI cutoff points for overweight and obese, calculated from the reference body mass, M° of the HRP, and the body mass thresholds as a function of height, 1.2M° and 1.4M°.
Cole et al [1] suggest BMI cutoff points which can be applied equally to Caucasian and Asian populations from 2 to 18 years, separately for girls and boys. Unfortunately, body mass and height are not reported separately.
The concept of the healthy reference population (HRP) and body mass excess relates the actual body mass, M, to the reference body mass, M°, at any given height in the HRP. BME cutoff points for overweight and obesity are at 1.2 and 1.4M° or BME of 0.2 and 0.4, respectively. The reference BMI° of the HRP increases with height (see Body mass excess [2]). Up to 13 years, girls and boys have the same height (Fig. 2). The BMI° of girls and boys increases from about 15 to 18 kg·m-2 from 5 to 13 years. In the following years, boys continue to grow and BMI° continues to increase to 20.5 kg·m-2, whereas growth of girls ceases and their BMI° remains at about 19 kg·m-2. This pattern applies to the HRP, and the comparison of the HRP [3, 4] with the data from Cole et al [1] is based on the assumption that the same height for age (Fig. 2) applies to both populations.
The BMI cutoff values of Cole et al (2010) agree closely with the BMI cutoff values derived from the BME-concept between age 8 and 13 (Fig. 1). Cole et al (2010) use identical BMI cutoff values for women and men at the age of 18, 25 kg·m-2 for overweight and 30 kg·m-2 for obesity. This ignores the fact that (1) women are smaller than men (see Height of humans), and (2) the BMI increases with height independent of a trend towards overweight (see Body mass excess). This explains, why lower BMI cutoff values are predicted from the BME-concept for women than men (Fig. 1).
Below the age of 8 years, the allometric phase changes to different exponents in the HRP. This is not taken into account in the approach of Cole et al (2010), which explains why their suggested cutoff values continue to drop more steeply with diminishing age compared to the HRP and the corresponding BME-linked cutoff values of the BMI (Fig. 1).
In summary, the BME cutoff values of 0.2 and 0.4 for overweight and obesity have several advantages over adjusted BMI cutoff points. BME cutoff values (1) are conceptually consistent, without first assuming an allometric exponent of 2 for the BMI and then adjusting the BMI cutoff point to take into account the fact that the actual allometric exponent of the HRP is different from 2, (2) apply equally to girls, boys and adult females and males, and (3) are easy to explain to the general public, since the values of the BME cutoffs make sense and are understandable: 20 % increased body mass at a given height for overweight; 40 % increased body mass at a given height for obese.


References

  1. Cole TJ, Bellizzi MC, Flegal KM, Dietz WH (2000) Establishing a standard definition for child overweight and obesity worldwide: international survey. BMJ 320:1240-3.
  2. Body mass excess
  3. WHO Multicentre Growth Reference Study Group (2006) WHO child growth standards based on length/height, weight and age. Acta Pædiatrica Suppl 450:76-85.
  4. 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.


Labels: MiParea: Gender, Developmental biology, Exercise physiology;nutrition;life style  Pathology: Obesity 

Organism: Human 

Preparation: Intact organism 




BMI, BME