Association of body image dissatisfaction with body mass index trajectory: the Adolescent Nutritional Assessment Longitudinal Study cohort

ABSTRACT Objective To examine the association of body image dissatisfaction (BID) with body mass index (BMI) trajectory among students from a metropolitan area of Rio de Janeiro. Methods Data were analyzed for 809 middle school students followed from 2010 to 2013, and 1131 high school students followed from 2010 to 2012. BID was assessed using a body silhouettes scale. Type of school (public and private) was used as a proxy of socioeconomic status. Results In the middle school cohort, girls from private schools who wanted to have smaller and bigger silhouettes gained fewer BMI units than those who were satisfied with their body image ( p < 0.05). In the high school, girls from private schools who wished to have bigger and smaller silhouettes experienced greater BMI increase than girls who were satisfied with their body image ( p < 0.05). Also, in the high school cohort, boys from public schools who wished to have smaller and bigger silhouettes experienced smaller BMI increase than boys who were satisfied ( p < 0.05). Conclusion BID may be related to the BMI trajectory in girls from private schools and in boys from public schools.

摘要 研究目的：探讨里约热内卢都会区学生的体像不满（body image dissatisfaction, BID）与体重指数（body mass index, BMI）变化轨迹的关联。方法：本研究分析了2010至2013年随访的809名初中生队列，以及2010至2012年随访的1131名高中生队列数据。采用体形容量表评估体像不满（BID），以学校类型（公立、私立）作为社会经济地位的替代指标。结果：在初中生队列中，私立学校中希望拥有更小或更大体型的女生，其体重指数增长值低于对自身体像满意的女生（p<0.05）。在高中生群体中，私立学校中希望拥有更大或更小体型的女生，其体重指数增幅高于对自身体像满意的女生（p<0.05）。此外，在高中生队列中，公立学校中希望拥有更小或更大体型的男生，其体重指数增幅低于对自身体像满意的男生（p<0.05）。结论：体像不满（BID）可能与私立学校女生、公立学校男生的体重指数（BMI）变化轨迹存在关联。