Stierman Bryan, Ogden Cynthia L, Yanovski Jack A, Martin Crescent B, Sarafrazi Neda, Hales Craig M
Division of Health and Nutrition Examination Surveys, National Center for Health Statistics, CDC, Hyattsville, MD, USA.
Epidemic Intelligence Service, CDC, Atlanta, GA, USA.
Am J Clin Nutr. 2021 Oct 4;114(4):1495-1504. doi: 10.1093/ajcn/nqab237.
Data from the NHANES indicate that BMI has increased in some subgroups of children and adolescents in the United States over the past 20 y; however, BMI is an indirect measure of body fatness.
We assessed changes in DXA-derived measures of adiposity in a nationally representative population of US children and adolescents aged 8-19 y from 1999-2006 to 2011-2018.
Using data from the NHANES, we compared the means and distributions of DXA-derived percentage body fat (%BF) and fat mass index (FMI; fat mass/height2 in kg/m2) between 1999-2006 (n = 10,231) and 2011-2018 (n = 6923) among males and females by age group, race and Hispanic origin, and BMI categories. Estimates were standardized by age and race and Hispanic origin.
From 1999-2006 to 2011-2018, mean %BF increased from 25.6% to 26.3% (change in %BF: 0.7%; 95% CI: 0.2%, 1.2%; P < 0.01) among all males, whereas mean %BF increased from 33.0% to 33.7% (change in %BF: 0.7%; 95% CI: 0.2%, 1.2%; P = 0.01) and mean FMI increased from 7.7 to 8.0 fat mass kg/m2 (change in FMI: 0.3 fat mass kg/m2; 95% CI: 0.0, 0.6 fat mass kg/m2; P = 0.02) among all females. Changes were not consistent across all age, race and Hispanic origin, and BMI categories. Both %BF and FMI increased among Mexican-American children and adolescents, but not other race and Hispanic origin groups.
Among US children and adolescents, DXA-derived measures of adiposity increased from 1999-2006 to 2011-2018, albeit not consistently in every age, race and Hispanic origin, and BMI subgroup. These data reinforce the need to consider other measures, besides BMI categories, when studying adiposity in children and adolescents.
美国国家健康与营养检查调查（NHANES）的数据表明，在过去20年中，美国儿童和青少年的一些亚组人群的体重指数（BMI）有所上升；然而，BMI是身体脂肪含量的间接测量指标。
我们评估了1999 - 2006年至2011 - 2018年期间，美国全国代表性的8至19岁儿童和青少年群体中，双能X线吸收法（DXA）得出的肥胖指标的变化情况。
利用NHANES的数据，我们比较了1999 - 2006年（n = 10231）和2011 - 2018年（n = 6923）期间，按年龄组、种族和西班牙裔血统以及BMI类别划分的男性和女性中，DXA得出的体脂百分比（%BF）和脂肪量指数（FMI；脂肪量/身高²，单位为kg/m²）的均值和分布情况。估计值按年龄、种族和西班牙裔血统进行了标准化。
从1999 - 2006年到2011 - 2018年，所有男性的平均%BF从25.6%增至26.3%（%BF变化：0.7%；95%置信区间：0.2%，1.2%；P < 0.01），而所有女性的平均%BF从33.0%增至33.7%（%BF变化：0.7%；95%置信区间：0.2%，1.2%；P = 0.01），平均FMI从7.7增至8.0脂肪量kg/m²（FMI变化：0.3脂肪量kg/m²；95%置信区间：0.0，0.6脂肪量kg/m²；P = 0.02）。在所有年龄、种族和西班牙裔血统以及BMI类别中，变化并不一致。墨西哥裔美国儿童和青少年的%BF和FMI均有所增加，但其他种族和西班牙裔血统群体则没有。
在美国儿童和青少年中，从1999 - 2006年到2011 - 2018年，DXA得出的肥胖指标有所增加，尽管并非在每个年龄、种族和西班牙裔血统以及BMI亚组中都一致。这些数据强化了在研究儿童和青少年肥胖问题时，除BMI类别外还需考虑其他测量指标的必要性。
