Pødenphant J, Gotfredsen A, Engelhart M, Andersen V, Heitmann B L, Kondrup J
Department of Medicine TTA, Rigshospitalet, National University Hospital, Copenhagen, Denmark.
Scand J Clin Lab Invest. 1996 Nov;56(7):615-25. doi: 10.3109/00365519609090596.
Body composition was determined by dual energy X-ray absorptiometry (DXA) scanning and classical reference methods (40K, 3H2O, and a combination of these in a four-compartment model) in 19 overweight patients with rheumatoid arthritis who underwent a 12-week weight-reducing regimen. The aim of the study was to investigate whether DXA provides a valid estimate of body composition. The results showed that weight as determined by DXA was highly significantly correlated to weight determined by scales. Furthermore, significant correlations were found in the body components (fat-free mass, fat mass) determined by DXA, 40K, 3H2O and the four-compartment model. Mean values differed slightly but significantly. With respect to changes in body composition, no significant correlations were found between any of the methods, except for the weight loss recorded by DXA and scales, and loss of fat mass (and fat free mass) estimated by 3H2O and the four-compartment model. The sparseness of correlations reflected the small changes in fat-free mass and fat mass (2.6 and 1.7 kg respectively), and the fact that changes were comparable to measurement errors of the various methods. We suggest that DXA scanning is a valid supplement for determination of body composition. Validation of DXA scanning requires new experimental in vitro investigations, which, incidentally, also applies to the classical reference methods.
采用双能X线吸收法（DXA）扫描和经典参考方法（40K、3H2O以及将这些方法结合应用于四室模型），对19例接受为期12周减重方案的超重类风湿关节炎患者进行身体成分测定。本研究的目的是调查DXA是否能有效评估身体成分。结果显示，DXA测定的体重与秤测量的体重高度显著相关。此外，DXA、40K、3H2O以及四室模型测定的身体成分（去脂体重、脂肪量）之间存在显著相关性。平均值略有差异但具有显著性。关于身体成分的变化，除了DXA和秤记录的体重减轻，以及3H2O和四室模型估计的脂肪量（和去脂体重）减少外，其他任何方法之间均未发现显著相关性。相关性较少反映出去脂体重和脂肪量的变化较小（分别为2.6 kg和1.7 kg），以及变化与各种方法的测量误差相当这一事实。我们认为DXA扫描是测定身体成分的有效补充方法。DXA扫描的验证需要新的体外实验研究，顺便说一句，这也适用于经典参考方法。
