BACKGROUND: A large incremental increase in BMI indicates excess fat deposition in most children, but the reference values for identifying those at risk for developing obesity have not been defined. AIM: To determine the mean and SD of annual incremental change (ΔSDS) in BMI for Japanese school children. SUBJECTS AND METHODS: A cohort of 669 Japanese children in one private school in Tokyo in whom height and weight were measured annually between 6-17 years of age. Each child's BMI was converted to SDS as based on the 1978-1981 Japanese references for the 12 annual measurements to derive the correlation coefficient, r, between two successive measurements. Using the formula, SD of ΔSDS = √2(1-r), the mean and SD of ΔSDS were obtained. RESULTS: Excess BMI gain was defined in terms of ΔSDS in Japanese children. Annual incremental increase greater than 2 SD of ΔSDS, equivalent to 1-2 BMI units/year for younger children and 2-3 BMI units/year for older children, respectively, indicates rapid increase in body fat in Japanese children. CONCLUSION: Based on analysis of incremental change in BMI in this cohort, a cut-off has been identified that can be used to identify children at risk for developing obesity.
BACKGROUND: A large incremental increase in BMI indicates excess fat deposition in most children, but the reference values for identifying those at risk for developing obesity have not been defined. AIM: To determine the mean and SD of annual incremental change (ΔSDS) in BMI for Japanese school children. SUBJECTS AND METHODS: A cohort of 669 Japanese children in one private school in Tokyo in whom height and weight were measured annually between 6-17 years of age. Each child's BMI was converted to SDS as based on the 1978-1981 Japanese references for the 12 annual measurements to derive the correlation coefficient, r, between two successive measurements. Using the formula, SD of ΔSDS = √2(1-r), the mean and SD of ΔSDS were obtained. RESULTS:Excess BMI gain was defined in terms of ΔSDS in Japanese children. Annual incremental increase greater than 2 SD of ΔSDS, equivalent to 1-2 BMI units/year for younger children and 2-3 BMI units/year for older children, respectively, indicates rapid increase in body fat in Japanese children. CONCLUSION: Based on analysis of incremental change in BMI in this cohort, a cut-off has been identified that can be used to identify children at risk for developing obesity.
Authors: David S Freedman; Hannah G Lawman; Deborah A Galuska; Alyson B Goodman; Gerald S Berenson Journal: Obesity (Silver Spring) Date: 2018-06-11 Impact factor: 5.002