Hankey Maria Stack, Miyazaki Yasuo
Virginia Tech, Fralin Biomedical Research Institute at VTC, 2 Riverside Circle, Roanoke, VA, 24016, USA.
Virginia Tech, School of Education, 1750 Kraft Drive, Room 2107, Blacksburg, VA, 24061, USA.
SSM Popul Health. 2019 Jul 17;8:100455. doi: 10.1016/j.ssmph.2019.100455. eCollection 2019 Aug.
Childhood obesity continues to be a major focus of public health efforts in the United States, where nearly 17% of children are obese. In this study, we focused on two significant features that characterize U.S. society-school mobility and a single-parent family structure-and how they relate to childhood obesity/overweight. Using a nationally representative sample from the Early Childhood Longitudinal Study-Kindergarten (ECLS-K) class of 1998, we examined the body mass index (BMI) growth trajectories of children to determine how these two key features interacted with demographic characteristics of gender, race/ethnicity, and socio-economic status (SES), which are known to be associated with BMI. We analyzed five waves of data from kindergarten through fifth grade of 9041 students applying a two-level hierarchical linear model (HLM). Results indicated that children who changed schools more than two times from kindergarten to fifth grade had higher BMI growth trajectories compared to children who changed only once or did not change schools. To our knowledge, no prior studies have examined this association. Results also indicated children in single-parent families were more likely to have higher BMI growth trajectories compared to children in two-parent families. Although both school mobility and family structure had an impact on children's BMI, we found that family structure had a larger impact than school mobility. Being in a two-parent family was a protective factor for children; that is, even if children in two-parent families moved schools twice or more, they still maintained a healthy BMI on average. For children in single-parent families, however, moving schools tended to have a greater, negative impact on their BMI statuses.
儿童肥胖问题仍然是美国公共卫生工作的主要关注点，该国近17%的儿童肥胖。在本研究中，我们聚焦于美国社会的两个显著特征——学校流动性和单亲家庭结构——以及它们与儿童肥胖/超重之间的关系。我们使用来自1998年幼儿园入学儿童纵向研究（ECLS-K）的全国代表性样本，考察了儿童的体重指数（BMI）增长轨迹，以确定这两个关键特征如何与已知与BMI相关的性别、种族/族裔和社会经济地位（SES）等人口统计学特征相互作用。我们运用二级分层线性模型（HLM）分析了9041名学生从幼儿园到五年级的五轮数据。结果表明，从幼儿园到五年级换校两次以上的儿童，其BMI增长轨迹高于只换校一次或未换校的儿童。据我们所知，此前尚无研究考察过这种关联。结果还表明，与双亲家庭的儿童相比，单亲家庭的儿童更有可能有较高的BMI增长轨迹。尽管学校流动性和家庭结构都对儿童的BMI有影响，但我们发现家庭结构的影响比学校流动性更大。处于双亲家庭对儿童是一个保护因素；也就是说，即使双亲家庭的儿童换校两次或更多次，他们的BMI平均仍保持健康。然而，对于单亲家庭的儿童来说，换校往往会对他们的BMI状况产生更大的负面影响。
