Institute of Nutrition and Food Technology (INTA), University of Chile, Santiago7830490, Chile.
Departamento Ciencias de la Salud, Carrera de Nutrición y Dietética, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago8940000, Chile.
Br J Nutr. 2021 Jul 14;126(1):37-42. doi: 10.1017/S0007114520003906. Epub 2020 Oct 8.
Assessing children's growth adequately is important due to the necessary prevention of adequate body composition, especially at pre-pubertal age. Simpler measurements such as anthropometry or bioimpedance, using equations validated in Caucasian children, have been demonstrated to overestimate or underestimate fat mass percentage (FM%) or fat-free mass (FFM) in Chilean children. In a sample of 424 children (198 boys and 226 girls) of 7-9 years old, the three component (3C) model was assessed, where total body water was determined by 2H dilution and body volume by air displacement plethysmography, in order to design and validate anthropometry and bioimpedance equations. The FM (%) equation specific for Chilean children was validated as (1·743 × BMI z-score) + (0·727 × triceps skinfold) + (0·385 × biceps skinfold) + 15·985, against the 3C model (R2 0·79). The new FFM equation (kg) generated was (log FFM = (0·018 × age) + (0·047 × sex) + (0·006 × weight) + (0·027 × resistance) + 2·071), with an R2 0·93 (female = 1 and male = 2). The Bland-Altman analysis shows a mean difference of 0·27 (sd 3·5) for the FM% in the whole group as well as 0·004 (sd 0·9) kg is the mean difference for the bioelectrical impedance analysis (BIA) FFM (kg) equation. The new equations for FM (%) and FFM (kg) in Chilean children will provide a simple and valid tool for the assessment of body composition in cohort studies or to assess the impact of nutritional programmes or public policies.
评估儿童的生长情况非常重要，因为这是预防儿童身体成分不足的必要手段，尤其是在青春期前。在智利儿童中，使用经过验证的白种人儿童方程的简单测量方法，如人体测量法或生物电阻抗法，已经被证明会高估或低估脂肪量百分比（FM%）或去脂体重（FFM）。在一个由 424 名 7-9 岁儿童（198 名男孩和 226 名女孩）组成的样本中，评估了三成分（3C）模型，其中通过 2H 稀释法确定全身总水量，通过空气置换体积描记法确定身体体积，以设计和验证人体测量法和生物电阻抗法方程。针对智利儿童的特定 FM%方程经过验证为（1·743×BMI z 分数）+（0·727×三头肌皮褶厚度）+（0·385×二头肌皮褶厚度）+15·985，与 3C 模型（R2 为 0·79）相吻合。生成的新 FFM 方程（kg）为（log FFM=（0·018×年龄）+（0·047×性别）+（0·006×体重）+（0·027×电阻）+2·071），R2 为 0·93（女性=1，男性=2）。Bland-Altman 分析显示，整个组的 FM%的平均差异为 0·27（sd 为 3·5），而 BIA FFM（kg）方程的平均差异为 0·004（sd 为 0·9）kg。智利儿童的新 FM%和 FFM（kg）方程将为队列研究中评估身体成分或评估营养计划或公共政策的影响提供一种简单有效的工具。
