Rendall M S, Weden M M, Fernandes M, Vaynman I
Department of Sociology, University of Maryland, College Park, MD 20742, USA.
Pediatr Obes. 2012 Dec;7(6):423-35. doi: 10.1111/j.2047-6310.2012.00080.x. Epub 2012 Aug 21.
The study aims to identify the ages contributing most to the development of higher obesity prevalence in the 8th grade (approximately age 14) among Hispanic and black children than among non-Hispanic white children in the United States.
Using the nationally representative Early Childhood Longitudinal Study (ECLS-K), a sample of 17,420 children in kindergarten in 1999, followed in 1st, 3rd, 5th and 8th grades through 2007, was analysed. First, 'normal', 'overweight' and 'obese' weight-status categories in each grade were assigned from US Centers for Disease Control body mass index percentiles. Second, probabilities of being in each of the three weight-status categories in kindergarten and of transitioning between categories after kindergarten were estimated by logistic regression. These probabilities were then used as parameters of a weight-status trajectory simulation model from which a decomposition analysis was performed.
Obesity prevalence in the 8th grade was equally high among Hispanic (25.0%, 95% confidence interval [CI]: 22.3, 27.8%) and black children (25.1%; 95% CI: 20.9, 29.6%) compared to white children (17.4%; 95% CI: 15.9, 19.0%). As much as 73% of the Hispanic-white 8th grade obesity disparity was generated by 3rd grade and 44% by kindergarten. In contrast, only 15% of the black-white obesity 8th grade disparity was generated by kindergarten, whereas 75% was generated between the 3rd and 8th grades and 53% between the 5th and 8th grades.
Although adolescent obesity is equally prevalent among Hispanic and black children, obesity emerges and is sustained earlier in Hispanic children. Diagnosis and prevention strategies should be designed accordingly.
本研究旨在确定在美国，西班牙裔和黑人儿童在八年级（约14岁）时肥胖患病率高于非西班牙裔白人儿童的主要年龄段。
使用具有全国代表性的儿童早期纵向研究（ECLS-K），分析了1999年幼儿园的17420名儿童样本，这些儿童在2007年之前分别接受了一年级、三年级、五年级和八年级的跟踪调查。首先，根据美国疾病控制中心的体重指数百分位数，为每个年级划分“正常”、“超重”和“肥胖”的体重状况类别。其次，通过逻辑回归估计幼儿园时处于三种体重状况类别之一的概率以及幼儿园后在不同类别之间转换的概率。然后将这些概率用作体重状况轨迹模拟模型的参数，在此基础上进行分解分析。
八年级时，西班牙裔儿童（25.0%，95%置信区间[CI]：22.3，27.8%）和黑人儿童（25.1%；95%CI：20.9，29.6%）的肥胖患病率与白人儿童（17.4%；95%CI：15.9，19.0%）相当。西班牙裔与白人八年级肥胖率差异的73%是由三年级造成的，44%是由幼儿园造成的。相比之下，黑人与白人八年级肥胖率差异中只有15%是由幼儿园造成的，而75%是在三年级至八年级之间造成的，53%是在五年级至八年级之间造成的。
尽管青少年肥胖在西班牙裔和黑人儿童中同样普遍，但肥胖在西班牙裔儿童中出现得更早且持续时间更长。应据此制定诊断和预防策略。
