Classification of obesity in children

A common classification of obesity in children is currently not available. In adults, the diagnosis of obesity is based on the calculation of BMI [the ratio of body weight (in kilograms) to the height of a person (in meters), squared]. According to BMI, you can overestimate the obesity of trained athletes or muscular children, nevertheless the calculation of BMI is the most reliable and reliable method of determining excess body weight. Other methods of assessing obesity are also used, but they are either very expensive (ultrasound, CT, MRI, X-ray absorptiometry), or require special equipment (caliper), or poorly reproduced (measurement of waist and hip extent), or do not have standards for childhood bioelectrical impedance analysis).

In children, the evaluation of the BMI is carried out taking into account age and sex according to the recommended standards. For the norm of the body weight take its value for the corresponding age. These guidelines are recommended by the WHO (Expert Committee on Clinical Guidelines for Overweight in Adolescent Preventive Services and the European Childhood Obesity Group) as a criterion for determining excess body weight in childhood.

Currently, anthropometric indicators are evaluated mainly in 2 ways: parametric, or sigma, and nonparametric - dental.

Parametric scale includes arithmetic mean ( "norm") departing from it, and measured value of the "sigma" (a - standard deviation, standard deviation - SD). To estimate the degree of difference of the investigated parameter from the mean values, calculate the standard deviation score (SDS). The indicator m ± SD is a region of average values, characteristic of approximately 68% of healthy children. The SDS value is from +1 to -1.

Excess body weight SDS corresponds to + 1- 2, obesity in children - +2 or more. In the group of children with obesity, two subgroups are distinguished:

• moderate obesity - SDS = 2.02-2.35;
• morbid (severe) obesity - SDS = 2.36-3.52.

There are special programs, for example Growth Analyzer 3.5, the Dutch Growth Foundation, which are evaluated in SDS units.

The advantage of the method lies in the possibility of evaluating and describing pronounced abnormalities, most often characterizing endocrine pathology. Values ranging from +2 SD (SDS = + 2) to -2 SD (SDS = -2) approximately correspond to the values from the 97th to the 3rd centile.

Dental tables (or graphs) show the quantitative limits of growth and body weight in a certain percentage, or percentage (centile), of children, depending on age. Since the centile method is not limited to the nature of the distribution, it is applicable to the evaluation of any indicators. The method is simple in operation, because when using centile tables, or graphs, any calculations are excluded.

Classification of body mass index in children and adolescents (WHO)

	Baptized BMI by age	Diagnosis
Less than 5		Deficiency of body weight
5-84		Normal body weight
85-94		Excess body weight
95 and above		Obesity

The children of the first 2 years of life use percentile tables of growth standards, body weight and head circumference separately for girls and boys, based on the measurement of a representative cohort of children of the European population. The growth and body weights obtained from this population of children are in complete agreement with the data of I.M. Mazurin et al., Obtained by examining the Russian population of children.

The percentile of growth (body weight, head circumference) is the mean (median of the 50th percentile) and deviation from the median, the 3th percentile corresponds to the lower limit of the norm (-2 SD from the mean), and the 97 percentile to the upper border of the norm (+2 SD of the mean).

[1], [2], [3], [4], [5], [6], [7], [8], [9],