The Study On Body Mass Index Centile Curves And The Reference Norm For Screening Overweight And Obesity In Kazak Primary And Middle School Students

Objective:To get body mass index,using LMS methods,description of centile curves,and to construct the percent of body mass index (BMI) for identifying overweight and obesity for Kazakh children aged 7¹8.In order to provide scientific foundation for Kazakh children as a preventive measure for obesity. Methods:The baseline survey was cross-sectional study,conducted in urban and rural areas of Altai city.Using cluster random sampling for the selected 2540 individuals,and measured gender,birth,height and weight;The BMI centile curves for Kazakh children aged 7¹8 were constructed byλ- median - coefficient of variation method (LMS);Based on recommendations of International Obesity Task Force (IOTF) and Chinese Working Group on Obesity( WGOC), the centile curves passing through 25 and 30 kg/m²,24 and 28 kg/m² at age 18 were set up as overweight and obesity cuts off points for Kazakh-children.By Student Physical Fitness Standard to survey obesity related factors among schoolchildren in Kazak.Results:The centile curve passing through 24 and 28 kg/m²at age 18 were P88.63 and P_98.28 for boys,and P_84.41 and P_98.12 for girls.Passing through 25 and 30 kg/m²at age 18 were P_92.96 and P_99.28 for boys,P_90.53 and P_99.38 for girls.Using WGOC standard for screening overweight rate of Kazakh children was 8.23%,obesity rate was 1.81%.Using this survey standard for screening overweight rate was 11.98%, obesity rate was 2.42%. Overweight rate of boys was 9.24%,and obesity rate was 2.74%.Overweight rate of girls was 14.52%,and obesity rate was 2.52%.By Logistic regression analysis,α= 0.05 is selected as variables for the significant level,father BMI,mother BMI,driking milk circumstances,eating fatty food circumstances, playing computer circumstances and eating fruit circumstances has statistical significance.Conclusion: There are geogrophic and ethnic differences of BMI distribution.Norm for screening overweight and obesity in Kazakh student was different from IOTF and WGOC,so for Kazak students,we recommend to use this study established BMI to cutoff ponits for screening overweight and obesity.The factors concerned with obesity are related to the inherited factors,food habit and lifestyle.