Abstract
Introduction. This study aims to describe the trends and racial/ethnic differences in prevalence of severe obesity among US children. Methods. We examined height and weight measurements from US children and adolescents aged 2 to 19 years using three National Health and Nutrition Examination Surveys (NHANES II: 1976–1980, N = 7 201, NHANES III: 1988–1994, N = 10 600, and NHANES 1999–2006, N = 15 980). We estimated the prevalence of severe obesity, defined as having a body mass index (BMI) above 35 kg/m2 or 120% of the age- and sex-specific 95th percentile on the CDC reference standards, stratified by sex and age groups (aged 2–5 years, 6–11 years, and 12–19 years). We compared prevalence estimates among non-Hispanic white, non-Hispanic black, and Hispanic children. Results. The age-standardized prevalence of severe obesity increased from 1.1%/1.3% (boys/girls) in NHANES II, to 2.9%/3.1% in NHANES III and 5.1%/4.7% in NHANES 1999–2006 (p-values for trend <0.001). We observed some differences in prevalence by race/ethnicity. Hispanic boys 6–11 years of age (9.0%, 95% CI: [6.4, 11.5]) and non-Hispanic black girls 12–19 years of age (12.6%, 95% CI: [10.6, 14.6]) had the highest prevalence of severe obesity in the most recent NHANES data. On average, obese youth were 9.7 kg (95% CI: [9.2, 10.2]) above the obesity standard, and severely obese youth were 21.3 kg (95% CI: [20.5, 22.3]) above. Conclusions. The prevalence of severe obesity among US youth is increasing, especially among Hispanic boys and non-Hispanic black girls. Our findings suggest that the degree of pediatric obesity is substantial and will likely have profound impact on adult morbid obesity and other morbidities.
Acknowledgements
We thank Dr. David Freedman at the Centers for Disease Control and Prevention for helpful input and discussions. An earlier version of this work was presented at the Annual Meeting of the Obesity Society in Phoenix, AZ in October 2008. This work was supported in part by grants from the Robert Wood Johnson Foundation (#260639) and the Centers for Disease Control and Prevention (U48/DP00064-00S1). This work is solely responsibility of the authors and does not represent official views of the Centers for Disease Control and Prevention.
Abbreviations
NHANES: National Health and Nutrition Examination Survey; BMI: Body Mass Index; CDC: Centers for Disease Control and Prevention.
Ethical approval
All analyses use de-identified, publicly available data and therefore no ethical approval is required.
Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.