Body composition assessment using DXA in six-year-old children: the 2004 Pelotas Birth Cohort, Rio Grande do Sul State, Brazil

The aim of this study was to describe fat (FM) and lean body mass (LBM) in six-year-old children from the 2004 Pelotas Birth Cohort, stratified by gender. Dual-Energy X-ray Absorptiometry was used to measure FM and LBM, FM and LBM indexes, and percentage (%) of FM and LBM. Mean measures of adiposity were higher among girls (6.3kg, 4.2kg/m2 and 23.4% vs. 5kg, 3.3kg/m2 and 18%) while LBM measures were higher among boys (19.3kg, 13kg/m2 and 78.5% vs. 17.7kg, 12.2kg/m2 and 73.2%). In both boys and girls mean measures of adiposity increased with socioeconomic status and maternal education. Mean measures of adiposity were higher among white-skinned children while %LBM was higher among black-skinned children. Preterm compared to full-term children showed lower mean measures of adiposity and LBM. Female sex, white skin color and higher socioeconomic conditions are associated with higher adiposity in childhood.

本研究旨在描述2004年佩洛塔斯出生队列（2004 Pelotas Birth Cohort）中6岁儿童的体脂量（Fat Mass，FM）与去脂体重（Lean Body Mass，LBM）情况，并按性别进行分层分析。本研究采用双能X射线吸收测定法（Dual-Energy X-ray Absorptiometry）测量了FM、LBM、体脂指数、去脂体重指数以及体脂百分比与去脂体重百分比。女孩的体脂含量平均测量值更高：分别为6.3kg、4.2kg/m²及23.4%，男孩则对应5kg、3.3kg/m²及18%；而去脂体重的平均测量值则以男孩更高：分别为19.3kg、13kg/m²及78.5%，女孩对应17.7kg、12.2kg/m²及73.2%。无论男孩还是女孩，体脂含量的平均测量值均随社会经济地位与母亲受教育程度的提升而升高。白人肤色儿童的体脂含量平均测量值更高，而去脂体重百分比则在黑人肤色儿童中更高。与足月出生儿童相比，早产儿童的体脂与LBM平均测量值均更低。女性性别、白人肤色以及更高的社会经济状况与儿童时期更高的体脂含量显著相关。