The Percentiles of Body Mass Index and Trend of Obesity in Schoolage Children in Seoul

ABSTRACT

PURPOSE: Many authors have reported that obesity is a serious health problem in schoolage children and adolescents and recently obese children are increasing. Accurate diagnosis is needed to estimate the prevalence rate and trend of obesity. We studied body mass index(BMI) percentile for age and sex as a reliable and valid screening for adiposity. METHODS: We measured weight and height of 33,329 schoolage children to estimate obesity according to body mass index(weight in kilograms/height in meters2) and different standard weight. We also calculated BMI percentiles according to age and sex. We defined obesity for screening purposes as body mass index(BMI) equal to or in excess of the 95th percentile for age and sex. We also compared the prevalence of obesity according to a different standard weight. RESULTS: The mean value of body mass index(BMI) increases with age and tends to be slightly higher for male than female subjects. The 95th percentiles of body mass index(BMI) ranges from 18.9kg/m2 to 28.2kg/m2 for both males and females. No significant differences were apparent in the mean value of body mass index for each year. CONCLUSION: The percentile curves of body mass index(BMI) will help pediatricians to determine the relative ranking of patients compared with large sample of healthy schoolage children. Further studies are needed to define a useful criteria for defining obesity using body mass index(BMI) in childhood and adolescence. A longitudinal study and nationwide sampling will be required to overcome the limitation of this cross-sectional study.