Martin Neovius1, Joanna Uddén, Erik Hemmingsson. 1. Department of Medicine, Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm, Sweden. Martin.neovius@ki.se
Abstract
PURPOSE: To compare estimates of change in percent body fat (Delta%BF) between DXA and BIA8 in abdominally obese women. METHODS: Six-month longitudinal study of 106 women (baseline: age 48.2 +/- 7.6 yr; BMI 30.4 +/- 2.9 kg.m; %BFDXA 45.8 +/- 3.6%) participating in an exercise-oriented behavior-change program (walking and bicycling). Fatness was measured by DXA and Tanita BC-418 (BIA8). Agreement between methods was assessed, and regression analysis was used to find predictors of the deviation between methods for estimating changes in fat mass percentage. RESULTS: The methods differed significantly, both at baseline and follow-up (-5.0 and -4.4%BF, respectively; both P < 0.001). The mean Delta%BF was -1.1 +/- 2.5%BFDXA and -0.5 +/- 2.2%BFBIA8 (mean difference between methods 0.6 +/- 1.8%BF; P < 0.001; 95% limits of agreement -3.0 to 4.2%BF), with a range of -14.8 to 3.3%BFDXA and -9.4 to 3.5%BFBIA8. Approximately 49% of the variation in the difference between methods was explained by variations in age (beta = -0.05; P = 0.006), DeltaBMI (beta = 0.98; P < 0.001), and Delta%BFDXA (beta = -0.71; P < 0.001), indicating that the larger the change, the greater the discrepancy between methods. CONCLUSION: The difference between methods regarding Delta%BF was statistically significant, but it was of small magnitude. However, with increasing Delta%BF, increasing discrepancies were observed, implying that the BIA equipment may have limited validity for detecting larger fat losses. Both clinicians and researchers may benefit from awareness of this potential limitation.
PURPOSE: To compare estimates of change in percent body fat (Delta%BF) between DXA and BIA8 in abdominally obesewomen. METHODS: Six-month longitudinal study of 106 women (baseline: age 48.2 +/- 7.6 yr; BMI 30.4 +/- 2.9 kg.m; %BFDXA 45.8 +/- 3.6%) participating in an exercise-oriented behavior-change program (walking and bicycling). Fatness was measured by DXA and Tanita BC-418 (BIA8). Agreement between methods was assessed, and regression analysis was used to find predictors of the deviation between methods for estimating changes in fat mass percentage. RESULTS: The methods differed significantly, both at baseline and follow-up (-5.0 and -4.4%BF, respectively; both P < 0.001). The mean Delta%BF was -1.1 +/- 2.5%BFDXA and -0.5 +/- 2.2%BFBIA8 (mean difference between methods 0.6 +/- 1.8%BF; P < 0.001; 95% limits of agreement -3.0 to 4.2%BF), with a range of -14.8 to 3.3%BFDXA and -9.4 to 3.5%BFBIA8. Approximately 49% of the variation in the difference between methods was explained by variations in age (beta = -0.05; P = 0.006), DeltaBMI (beta = 0.98; P < 0.001), and Delta%BFDXA (beta = -0.71; P < 0.001), indicating that the larger the change, the greater the discrepancy between methods. CONCLUSION: The difference between methods regarding Delta%BF was statistically significant, but it was of small magnitude. However, with increasing Delta%BF, increasing discrepancies were observed, implying that the BIA equipment may have limited validity for detecting larger fat losses. Both clinicians and researchers may benefit from awareness of this potential limitation.
Authors: Sergey Rudnev; Jane S Burns; Paige L Williams; Mary M Lee; Susan A Korrick; Tatiana Denisova; Yuri Dikov; Gennady Kozupitsa; Russ Hauser; Oleg Sergeyev Journal: Clin Nutr ESPEN Date: 2019-11-16
Authors: Muhammad Aslam; Aaron W Eckhauser; Cindy A Dorminy; Cynthia M Dossett; Leena Choi; Maciej S Buchowski Journal: Obes Res Clin Pract Date: 2009-11-01 Impact factor: 2.288
Authors: Kari Johansson; Erik Hemmingsson; Richard Harlid; Ylva Trolle Lagerros; Fredrik Granath; Stephan Rössner; Martin Neovius Journal: BMJ Date: 2011-06-01
Authors: Kari Johansson; Martin Neovius; Ylva Trolle Lagerros; Richard Harlid; Stephan Rössner; Fredrik Granath; Erik Hemmingsson Journal: BMJ Date: 2009-12-03