青春发育期肥胖儿童与体重正常儿童身体成分的变化

Changes in body composition of obese children and it′s comparison with normal-weight children during puberty development

目的比较青春发育期体重正常和肥胖儿童青少年身体成分、非脂肪组织指数（fat-free mass index，FFMI）和脂肪组织指数（fat mass index，FMI）及其随年龄变化趋势和性别差异。方法选择7～15岁体重正常和肥胖儿童356名，每组各性别、年龄约10名，采用DEXA法测定身体成分，根据公式FFMI（kg·m^-2）=非脂肪组织（FFM）（kg）／身高（m）^2，FMI（kg·m^-2）=脂肪组织（FM）（kg）／身高（m）^2计算FFMI和FMI。结果各年龄组男、女生肥胖儿童身体成分中脂肪组织和去脂肪组织的实测值均高于体重正常儿童（P〈0．05）。7～15岁肥胖儿童FFMI和FMI均随年龄增长而增加，并高于同性别、同年龄组体重正常儿童，差异有统计学意义（P〈0．05）。结论肥胖儿童脂肪组织、去脂肪组织含量、FFMI、FMI，与体重正常儿童存在差异，男女间差异明显；FFMI和FMI是肥胖儿童的体重管理中值得应用的监测指标。

Objective To make a comparison on body composition, fat mass index （FMI） and fat free mass index （FFMI） , their changes with growth and sexual differentiation between obese and normal - weight children during puberty development. Methods 356 boys and girls aged 7 - 15 years were included in this study and for each age and sexual group, both normal - weight and obese children were about 10 who received a measurement of body composition with dual - energy x - ray absorptiometry （DEXA）. FF- MI and FMI were calculated according to following expressions： FFMI （ kg · m^-2 ） = FFM （kg） /height （m）^2andFMI（kg·m^-2） =FM （kg） /height （m）^2. Results Both fat mass and fat free mass of obese children were significantly higher than those of normal - weight children （P 〈 0. 05 ）. Both FMI and FFMI of obese children increased with age and were higher than those of normal - weight children with same sex and age group significantly （ P 〈 0. 05）. Conclusion Differences existed in the quantity of fat mass, fat free mass, FMI and FFMI between obese and normal - weight children and sexual differentiation was significant. FFMI and FMI are valuable indexes for surveillance in the weight management of obese children.