Hoffman Daniel J, Sawaya Ana L, Martins Paula A, McCrory Megan A, Roberts Susan B
Department of Nutritional Science, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA.
Pediatrics. 2006 Apr;117(4):e725-32. doi: 10.1542/peds.2005-0779.
The use of anthropometric measures (eg, skinfold thicknesses, BMI) to assess obesity is not without controversy and has not been explored with respect to the use among groups of children with growth retardation (ie, stunting). Therefore, the objective of this study was to determine whether growth retardation affects the accuracy of field methods for assessing body composition in children.
A cross-sectional study was conducted in 30 stunted children and 30 nonstunted children who were matched for age- and weight-for-height z score and living in the shantytowns of São Paulo, Brazil. Body composition (fat mass, fat-free mass, and percentage of body fat [%BF]) was measured by H2(18)O dilution (reference technique) using group-specific values for the hydration of fat-free mass and dual-energy x-ray absorptiometry. BMI and body composition that were calculated from 3 pediatric skinfold prediction equations were evaluated for accuracy of %BF in comparison with the reference technique.
Stunted children were shorter and weighed less than nonstunted children, but BMI did not differ significantly between groups. All 3 skinfold equations tested resulted in a calculated %BF that was significantly lower than that measured by H2(18)O dilution for both stunted and nonstunted groups, and %BF as calculated by any of the skinfold equations tested did not significantly predict %BF by H2(18)O dilution. In contrast, BMI significantly predicted %BF in both stunted and nonstunted children, and this relationship did not differ by growth status.
BMI but not skinfolds significantly predicted %BF measured by H2(18)O dilution. The relationship between BMI and %BF did not differ between stunted and nonstunted children; this indicates that BMI can be used in field studies of obesity and stunting. However, the prediction of %BF by BMI is relatively poor in both groups of children, and continued investigation of more accurate field methods for measuring %BF is warranted.
使用人体测量指标（如皮褶厚度、体重指数）评估肥胖并非毫无争议，且尚未在发育迟缓（即发育不良）儿童群体中进行过相关探讨。因此，本研究的目的是确定发育迟缓是否会影响儿童身体成分评估现场方法的准确性。
对30名发育不良儿童和30名非发育不良儿童进行了一项横断面研究，这些儿童年龄和身高别体重Z评分相匹配，居住在巴西圣保罗的棚户区。采用H2(18)O稀释法（参考技术）测量身体成分（脂肪量、去脂体重和体脂百分比[％BF]），使用针对去脂体重水合作用的组特异性值和双能X线吸收法。将根据3个儿科皮褶预测方程计算得出的体重指数和身体成分与参考技术相比，评估其预测％BF的准确性。
发育不良儿童比非发育不良儿童更矮、体重更轻，但两组之间的体重指数没有显著差异。所测试的所有3个皮褶方程计算得出的％BF均显著低于发育不良组和非发育不良组通过H2(18)O稀释法测得的％BF，且所测试的任何皮褶方程计算得出的％BF均不能显著预测通过H2(18)O稀释法测得的％BF。相比之下，体重指数在发育不良和非发育不良儿童中均能显著预测％BF，且这种关系不受生长状况的影响。
体重指数而非皮褶厚度能显著预测通过H2(18)O稀释法测得的％BF。发育不良和非发育不良儿童之间体重指数与％BF的关系没有差异；这表明体重指数可用于肥胖和发育迟缓的现场研究。然而，两组儿童中体重指数对％BF的预测相对较差，因此有必要继续研究更准确的现场测量％BF的方法。
