BACKGROUND: Little information is available on the assessment of changes in body composition as a function of weight change with the use of the fan beam of dual-energy X-ray absorptiometry (DXA). OBJECTIVE: The objective was to determine the accuracy of the fan beam of the QDR 4500A densitometer and the pencil beam of the QDR 2000 densitometer in estimating changes in whole-body lean soft tissue mass (LSTM(DXA)) and fat mass (FM) with weight change. DESIGN: Thirty-seven subjects who lost 5.7 +/- 4.5 kg were measured before and after weight change. Using total body water and computed tomography (CT) of the midthigh, we compared changes in FFM(TBW) and LSTM(CT) with changes in LSTM(DXA). RESULTS: Overall, compared with TBW, the fan beam gave a larger estimate of change (macro x +/- SD) in LSTM (fan beam - TBW: -0.7 +/- 1.6 kg) than did the pencil beam (pencil beam - TBW: -0.1 +/- 1.6 kg). When the change in LSTM obtained with the fan beam and pencil beam was regressed against the change in FFM(TBW), the slope of the line for the fan beam was 0.97 (r(2) = 0.61) and that for the pencil beam was 0.86 (r(2) = 0.61). Regression analysis showed that the results between the 2 units were not interchangeable. For the midthigh region, the change in LSTM(CT) was moderately correlated with the change in LSTM(DXA) with the fan beam and pencil beam. CONCLUSIONS: The measurement of change in LSTM with the fan and pencil beams provides the same relation to changes in FFM assessed by TBW, but the 2 systems are not interchangeable.
BACKGROUND: Little information is available on the assessment of changes in body composition as a function of weight change with the use of the fan beam of dual-energy X-ray absorptiometry (DXA). OBJECTIVE: The objective was to determine the accuracy of the fan beam of the QDR 4500A densitometer and the pencil beam of the QDR 2000 densitometer in estimating changes in whole-body lean soft tissue mass (LSTM(DXA)) and fat mass (FM) with weight change. DESIGN: Thirty-seven subjects who lost 5.7 +/- 4.5 kg were measured before and after weight change. Using total body water and computed tomography (CT) of the midthigh, we compared changes in FFM(TBW) and LSTM(CT) with changes in LSTM(DXA). RESULTS: Overall, compared with TBW, the fan beam gave a larger estimate of change (macro x +/- SD) in LSTM (fan beam - TBW: -0.7 +/- 1.6 kg) than did the pencil beam (pencil beam - TBW: -0.1 +/- 1.6 kg). When the change in LSTM obtained with the fan beam and pencil beam was regressed against the change in FFM(TBW), the slope of the line for the fan beam was 0.97 (r(2) = 0.61) and that for the pencil beam was 0.86 (r(2) = 0.61). Regression analysis showed that the results between the 2 units were not interchangeable. For the midthigh region, the change in LSTM(CT) was moderately correlated with the change in LSTM(DXA) with the fan beam and pencil beam. CONCLUSIONS: The measurement of change in LSTM with the fan and pencil beams provides the same relation to changes in FFM assessed by TBW, but the 2 systems are not interchangeable.
Authors: Andrea P Rossi; Nora L Watson; Anne B Newman; Tamara B Harris; Stephen B Kritchevsky; Douglas C Bauer; Suzanne Satterfield; Bret H Goodpaster; Mauro Zamboni Journal: J Gerontol A Biol Sci Med Sci Date: 2011-04-15 Impact factor: 6.053
Authors: Ann V Schwartz; Deborah E Sellmeyer; Eric Vittinghoff; Lisa Palermo; Beata Lecka-Czernik; Kenneth R Feingold; Elsa S Strotmeyer; Helaine E Resnick; Laura Carbone; Brock A Beamer; Seok Won Park; Nancy E Lane; Tamara B Harris; Steven R Cummings Journal: J Clin Endocrinol Metab Date: 2006-04-11 Impact factor: 5.958
Authors: Jung Sun Lee; Marjolein Visser; Frances A Tylavsky; Stephen B Kritchevsky; Ann V Schwartz; Nadine Sahyoun; Tamara B Harris; Anne B Newman Journal: J Gerontol A Biol Sci Med Sci Date: 2009-04-14 Impact factor: 6.053
Authors: Jane Elberg; Jennifer R McDuffie; Nancy G Sebring; Christine Salaita; Margaret Keil; Delphine Robotham; James C Reynolds; Jack A Yanovski Journal: Am J Clin Nutr Date: 2004-07 Impact factor: 7.045
Authors: Seok Won Park; Bret H Goodpaster; Jung Sun Lee; Lewis H Kuller; Robert Boudreau; Nathalie de Rekeneire; Tamara B Harris; Stephen Kritchevsky; Frances A Tylavsky; Michael Nevitt; Yong-wook Cho; Anne B Newman Journal: Diabetes Care Date: 2009-06-23 Impact factor: 19.112