Okasora K, Takaya R, Tokuda M, Fukunaga Y, Oguni T, Tanaka H, Konishi K, Tamai H
Department of Pediatrics, Osaka Medical College, Japan.
Pediatr Int. 1999 Apr;41(2):121-5. doi: 10.1046/j.1442-200x.1999.4121048.x.
There are a variety of methods for assessing body composition. Bioelectrical impedance analysis (BIA) is an easy and non-invasive technique, but has limitations in underweight and overweight subjects. Few reports have investigated the validity of BIA in children. In this report, the characteristics of BIA, especially in overweight and underweight children, are assessed and the results are compared with those of dual energy X-ray absorptiometry (DXA), as a reliable method for assessing body composition.
Determination of the fat-free mass (FFM), body fat content and percent body fat (%fat) was carried out using both BIA and DXA. The subjects (60 males and 44 females) were divided into five groups according to the percentage of ideal bodyweight (%IBW). Ten obese children, who were treated with exercise and a low-energy diet for 1 month, were also enrolled in this study.
The %fat, FFM and body fat content showed a close correlation when measured by BIA and DXA with the correlation coefficients being 0.90, 0.95, and 0.95, respectively. In the underweight group, the %fat value determined by BIA tended to be greater than that determined by DXA, while in the overweight group, the BIA value was lower than the DXA value. The same trend was also seen in obese children before and after therapy with exercise and diet.
Bioelectrical impedance analysis seems to be a reasonable method for daily clinical use, but attention should be paid to the interpretation of %fat values in underweight and overweight children.
评估身体成分有多种方法。生物电阻抗分析（BIA）是一种简便且无创的技术，但在体重过轻和超重的受试者中存在局限性。很少有报告研究BIA在儿童中的有效性。在本报告中，评估了BIA的特点，尤其是在超重和体重过轻儿童中的特点，并将结果与双能X线吸收法（DXA）进行比较，DXA是评估身体成分的可靠方法。
使用BIA和DXA测定无脂肪量（FFM）、体脂含量和体脂百分比（%fat）。根据理想体重百分比（%IBW）将受试者（60名男性和44名女性）分为五组。本研究还纳入了10名肥胖儿童，他们接受了1个月的运动和低能量饮食治疗。
通过BIA和DXA测量时，%fat、FFM和体脂含量显示出密切相关性，相关系数分别为0.90、0.95和0.95。在体重过轻组中，BIA测定的%fat值往往高于DXA测定的值，而在超重组中，BIA值低于DXA值。在肥胖儿童运动和饮食治疗前后也观察到了相同的趋势。
生物电阻抗分析似乎是日常临床使用的合理方法，但在体重过轻和超重儿童中应注意对%fat值的解读。
