Body composition in underweight elderly subjects: reliability of bioelectrical impedance analysis.

摘要: Abstract Background & aims : In underweight elderly subjects it is important to estimate body composition and particularly fat-free mass (FFM). Bioelectrical impedance analysis (BIA) a non-invasive method in determining FFM, but its usefulness these frail should be verified. The aim of this study verify people the reliability previously published BIA formulas detecting FFM. Methods Fifty-seven hospitalized (27 males 30 females) with index 2 were selected. all subjects, FFM was detected by dual energy X-ray absorptiometry. Moreover, measurements performed at standard frequency (50kHz 800μA) derived using main previous equations. Results men, Kyle Rising equations gave acceptable estimates mean error, respectively, 1±1.9 1.4±1.7kg. Also RJL formula could used after adjusting for correction factor. women, no equation seemed sufficiently reliable Conclusions seems useful evaluate men have intrinsic limits women. Nevertheless, variability behavior different suggests careful adopting