Department of Exercise Science, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA.
Ethn Health. 2021 Nov;26(8):1180-1195. doi: 10.1080/13557858.2019.1591349. Epub 2019 Mar 8.
Low-income children (6-19 years) are at higher risk for BMI-determined overweight and obesity, but this relationship varies by children's race/ethnicity. BMI, however, is a poor marker of excess adiposity in minority children. The objective of this study was to determine if the relationships of income and/or race/ethnicity with weight status was consistent between BMI-determined overweight or obesity and adiposity measured via dual energy X-ray absorptiometry (DXA). This study included a nationally representative sample of U.S. children ( = 9857, 14.0 years, 52.8% male, 31.8% low-income, 52.1% middle-income). Disparities in household income-to-poverty ratio (low-income = 0.00-1.00, middle-income = 1.01-4.00, high-income > 4.00) was the exposure with prevalence of BMI-determined overweight or obesity (i.e. age/sex specific CDC cutoffs) and DXA-determined excess adiposity (i.e. body fat%≥75th percentile) as the outcome. For DXA, children from high-income households were 0.47 (95CI = 0.35, 0.65) and 0.55 (95CI = 0.44, 0.70) times as likely to have excess adiposity compared to children in middle and low-income households, respectively. Similar findings were observed with BMI-determined overweight and obesity. Stratified analyses by individual racial/ethnic groups showed children from high-income households were less likely to have excess adiposity compared to their low-income peers for White, Black, and Hispanic children. However, these relationships did not hold for BMI-determined overweight and obesity in Black and Hispanic children. This study revealed that the relationships between income and DXA-determined adiposity differed from the relationships between income and BMI-determined overweight and obesity for children who are Black and Hispanic. This suggests that BMI may be an inappropriate surveillance tool when exploring relationships between race/ethnicity, income, and adiposity.
低收入儿童（6-19 岁）超重和肥胖的风险更高，但这种关系因儿童的种族/民族而异。然而，BMI 是衡量少数族裔儿童肥胖程度的一个较差指标。本研究的目的是确定收入和/或种族/民族与体重状况的关系，是否在 BMI 确定的超重或肥胖与双能 X 射线吸收法（DXA）测量的肥胖程度之间保持一致。本研究包括了一个具有全国代表性的美国儿童样本（=9857 名，14.0 岁，52.8%为男性，31.8%为低收入，52.1%为中等收入）。家庭收入与贫困比率的差异（低收入=0.00-1.00，中等收入=1.01-4.00，高收入>4.00）是暴露因素，BMI 确定的超重或肥胖（即年龄/性别特定的 CDC 切点）和 DXA 确定的肥胖（即体脂肪%≥第 75 百分位数）是结果。对于 DXA，来自高收入家庭的儿童与中低收入家庭的儿童相比，发生肥胖的可能性分别高出 0.47（95%CI=0.35, 0.65）和 0.55（95%CI=0.44, 0.70）倍。用 BMI 确定的超重和肥胖也观察到了类似的发现。按个体种族/族裔群体进行分层分析显示，与低收入同龄人相比，来自高收入家庭的白种人、黑人和西班牙裔儿童肥胖的可能性较小。然而，黑人和西班牙裔儿童的 BMI 确定的超重和肥胖与这些关系并不成立。本研究表明，对于黑人和西班牙裔儿童，收入与 DXA 确定的肥胖之间的关系与收入与 BMI 确定的超重和肥胖之间的关系不同。这表明 BMI 可能不是探索种族/民族、收入和肥胖之间关系的适当监测工具。
