Battistini N, Brambilla P, Virgili F, Simone P, Bedogni G, Morini P, Chiumello G
Cattedra di Fisiologia della Nutrizione, Università di Modena, Italy.
Int J Obes Relat Metab Disord. 1992 Mar;16(3):207-12.
Almost all formulae for the prediction of total body water (TBW) from body impedance are based on the assumption of a constant conductor configuration--i.e. a constant subject section. In this paper we report on data obtained for a group of 19 young obese subjects (relative weight greater than 120%) and 10 young normal subjects (relative weight 80-110%). In obese subjects, the application of two different formulae generated from normal children gave biased results and led to an underestimation of TBW with respect to the reference value obtained by deuterium oxide dilution. Body mass index accounted for more than 40% of the inter-individual variability, suggesting that body size was not taken sufficiently into consideration by the predictive formulae used. We have used the body surface area as the anthropometrical parameter for the prediction of TBW from body impedance. The regression formula that we propose (TBW = 1.156 x (surface area/body impedance) - 2.356; R = 0.96), although requiring further validation on external populations, seems to provide a more realistic assessment of TBW in young obese subjects. We therefore suggest that the assessment of TBW in young obese subjects requires specifically designed prediction formulae.
几乎所有通过人体阻抗预测总体水（TBW）的公式都是基于导体配置恒定的假设——即受试者截面恒定。在本文中，我们报告了一组19名年轻肥胖受试者（相对体重超过120%）和10名年轻正常受试者（相对体重80 - 110%）的数据。在肥胖受试者中，应用从正常儿童得出的两种不同公式得出的结果有偏差，导致相对于通过氧化氘稀释获得的参考值，TBW被低估。体重指数占个体间变异性的40%以上，这表明所使用的预测公式没有充分考虑体型因素。我们已将体表面积作为从人体阻抗预测TBW的人体测量参数。我们提出的回归公式（TBW = 1.156×（表面积/人体阻抗） - 2.356；R = 0.96），尽管需要在外部人群中进一步验证，但似乎能更实际地评估年轻肥胖受试者的TBW。因此，我们建议对年轻肥胖受试者的TBW评估需要专门设计的预测公式。
