Wang H, Xue H, Du S, Zhang J, Wang Y, Zhang B
National Institute for Nutrition and Health, Chinese Center for Disease Control and Prevention, Beijing, China.
Department of Epidemiology and Environmental Health, School of Public Health and Health Professions, University at Buffalo, State University of New York, Buffalo, NY, USA.
Int J Obes (Lond). 2017 Jun;41(6):964-970. doi: 10.1038/ijo.2017.53. Epub 2017 Feb 27.
Research on the shift in children's body mass index (BMI) distribution is limited and conditional mean models used in the previous research have limitations in capturing cross-distribution variations in effects. The objectives are to analyze the shift in Chinese children's BMI distribution and to test the associations between BMI distribution and other factors.
We analyzed data collected from children 7 to 17 years old from the China Health and Nutrition Survey (CHNS) conducted in 1997, 2000, 2004, 2006, 2009 and 2011, from 2814 participants with 6799 observations. Longitudinal quantile regression (QR) was used to explore the effect of several factors on BMI trends in 2015.
The BMI curves shift to the right in boys and girls, with the distributions becoming wider, indicating a higher proportion of children have become overweight. The 5th, 15th, 50th, 85th and 95th BMI percentile curves all shifted upward from 1997 to 2011, and the higher percentiles had greater increases. The prevalence of overweight and obesity increased in boys and girls between 1997 and 2011, from 6.5 to 15.5% in boys and from 4.6 to 10.4% in girls. Energy intake and parents' BMI levels had a positive association with children's BMI. Per capita income was positively associated with changes in BMI only at the upper percentiles of the BMI distributions in boys. Increased physical activity (PA) was associated with decreased BMI in girls.
Children in China are becoming increasingly overweight. Energy intake, parental BMI, PA and early menarche age in girls are associated with elevated BMI in children.
关于儿童体重指数（BMI）分布变化的研究有限，且先前研究中使用的条件均值模型在捕捉效应的交叉分布差异方面存在局限性。目的是分析中国儿童BMI分布的变化，并检验BMI分布与其他因素之间的关联。
我们分析了1997年、2000年、2004年、2006年、2009年和2011年中国健康与营养调查（CHNS）中7至17岁儿童的数据，共2814名参与者，6799次观测。采用纵向分位数回归（QR）来探讨2015年几个因素对BMI趋势的影响。
男孩和女孩的BMI曲线均向右移动，分布变宽，表明超重儿童的比例更高。从1997年到2011年，第5、15、50、85和95百分位的BMI曲线均向上移动，百分位数越高，增长幅度越大。1997年至2011年期间，男孩和女孩超重和肥胖的患病率均有所增加，男孩从6.5%增至15.5%，女孩从4.6%增至10.4%。能量摄入和父母的BMI水平与儿童的BMI呈正相关。人均收入仅在男孩BMI分布的较高百分位数上与BMI变化呈正相关。增加身体活动（PA）与女孩BMI降低有关。
中国儿童超重现象日益严重。能量摄入、父母BMI、PA和女孩初潮年龄与儿童BMI升高有关。
