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w Vol. 9, No. 1 October 2009 pp. 52-58» w w» y ½ Á x*á Á w w ƒ w š w Comparison of Accuracy of Body Composition Analyzer using Bioelectrical Impedance Analysis Moon Chul Kim, Jee Hyun Kang *, Young Seok Kang and ByungYeon Yu Department of Family Medicine, College of Medicine, Konyang University Abstract: Background: Various body composition analysis instruments using bioelectrical impedance analysis (BIA) have been used widely in clinical setting. However, few studies have examined the accuracy of these instruments. Methods: To compare the accuracy of percent body fat (PBF) and visceral fat areas (VFA) measured by two body composition analysis instruments using BIA [InBody720 (Biospace, Korea) and X-scan plus (Jawon Medical, Korea)] against PBF by dual-energy x-ray absortiometry (DXA), VFA by abdominal computed tomogram (CT), 100 adults (male 55, female 45) who visited a health examination center were enrolled in this study. Results: The coefficient of correlation in PBF measured by Inbody720 and X-scan plus based on DXA were 0.922 and 0.897 respectively, and there was statistically significant difference between these correlation coefficients (p<0.001). The coefficient of correlation in visceral fat area (VFA) measured by Inbody720 and X-scan plus based on the abdominal CT were 0.599 and 0.485 respectively, and these difference of correlation coefficients did not reach the statistical significance (p = 0.26). In the analysis of agreement using Bland-Altman plot, the limits of agreement in value of BPF based on DXA were 0.3±3.2% in Inbody720 and 1.1±3.8% in X-scan plusii. Moreover, the limits of agreement in value of VFA based on CT were 11.8±59.9 cm 2 in Inbody720 and 2.0±73.2 cm 2 in X-scan plus II. Conclusion: Although both BIA instruments compared favorably with DXA, the correlation coefficient in PBF measured by Inbody720 was statistically higher than those measured by X-scan plus II in this study group. Keywords: Bioelectrical impedance analysis, Dual energy X-ray absortiometry, Computer tomography, Body composition analysis, Visceral fat area. w» w ù (kg/m 2 )ƒ ƒ š, t (1-3). ù ü v w k, š» yw w d v (4,5). w w p, ü ƒ», y x sƒw ü d w (6-14). d w» w (Dual energy X-ray absortiometry, DXA),, e *Corresponding Author: Email: jeehyunkang@yahoo.co.kr Tel: +82-42-600-8808; Fax: +82-42-600-9095, d, y y, q, ful d (Computer tomography, CT),»œ w. d w wš f v w rw š.» w (Bioelectrical Impedance Analysis, BIA) wš ƒ w, rwš w s š, DXA CT» BIA d e y w ƒ (15-16). BIA w»ƒ ü q š, BIA»» y w (17) Inbody3.0 nbody-1 w w ƒ.,, d InBody720 (Biospace, Korea) X-scan plusii (Jawon Medical, Korea)ƒ DXA» w e ùkü, š» ü d w ü CT» y w ƒ» w w.

» w w» y 53 1. 2007 w w l w 20~64 û 100 w š, w š v w. -ks wz» 23 kg/cm 2 š, šx, š x x y, y (18). 2. 1) d d ww w y w d. 8 œ k k z ƒ š k w 0.1 cm, 0.1 kg¾ d w, (kg) (meter) ù w. x v ƒ r ü k 25Ê30 cm š ³ jš, s ò WHO «w w w 0.1 cm ¾ d w (3). 2) d» w w d w š, ƒ» InBody720 (Biospace, Korea) X-scan plusii (Jawon Medical, Korea) w. DXA lunar Prodigy (Lunar co., Madison, USA) w l ó¾ z w.» w w» d w,. ù,,,» w z v ƒ d t e k, q rš š ww»» ü mw ü. 3) ü d ü d ful d (CT, SOMATOM Plus4, Siemens, Gemany) InBody720 (Biospace, Korea), š X- scan plusii (Jawon Medical, Korea) w ww. CT w ü d v ƒ k q š, 4 5 z w Housfield Unit 30~ 190 w d w w z w.» d w ü d w. 3. m Independent t-test w p ƒ w. ü d ƒ w» w paired t-test ww. DXA BIA w d e, š CT BIA d w ü Pearson w w š txw. Medcalc m v comparison of correlation coefficient w. e w» w DEX CT» Bland-Altman plots w, d e x w s³±t r w. m v SPSS for window V 12.0 (SPSS Inc., USA) Medcalc software V8.2 (Mariakerke, Belgium) w, 0.05 w. 1. p 28 l 65 ¾ s³ 46.05± 8.87 š, 100 û ƒ 55 (55%), ƒ 45 (45%). û ƒƒ 26.8±2.1(kg/cm 2 ), 25.1Û2.2(kg/cm 2 ), û ü, x,, w y. de d d e Table 1. Table 1. General characteristics and body composition of the study subjects. Variable Male (N = 55) Female (N = 45) Mean±SD Mean±SD p-value * Age (years) 45.3±9.2 47.0±8.5 0.343 Height (cm) 170.0±5.8 155.9±6.7 < 0.001 Weight (kg) 77.5±8.9 61.1±7.6 < 0.001 Waist (cm) 90.3±6.2 84.0±6.6 < 0.001 BMI (kg/cm 2 ) 26.8±2.1 25.1±2.2 < 0.001 VFA-CT (cm 2 ) 119.8±39.1 86.0±26.7 < 0.001 VFA-Inbody (cm 2 ) 128.7±23.0 101.3±21.5 < 0.001 VFA-X-scan (cm 2 ) 128.1±29.8 80.3±21.9 < 0.001 PBF-DXA (%) 26.1±4.4 34.4±3.8 < 0.001 PBF-Inbody (%) 26.7±4.3 35.0±4.1 < 0.001 PBF-X-scan (%) 25.9±3.4 32.1±3.4 < 0.001 BFM-DXA (kg) 20.6±5.2 21.4±3.7 0.418 BFM-Inbody (kg) 21.0±4.7 21.7±3.6 0.402 BFM-X-scan (kg) 20.1±4.0 19.7±3.2 0.575 LBM-DXA (kg) 54.8±5.3 38.3±5.1 < 0.001 LBM-Inbody (kg) 54.0±5.8 38.2±5.3 < 0.001 LBM-X-scan (kg) 52.2±6.8 38.2±5.0 < 0.001 BMI: body mass index, DXA: dual energy X-ray absortiometry, VFA-CT: visceral fat area measured by computer tomography, VFA-I: visceral fat area measured by Inbody720, VFA-X: visceral fat area measured by X-scan plus II, PDF: percent body fat, BFM: body fat mass, LBM: lean body mass. * by Independent t-test.

54 ½ Á xá Á Table 2. Mean differences of the measured by Dual energy X-ray absorptiometry, Inbody and X-scan plus II according to variable. Body composition Variable Percent body fat (%) Body fat mass (kg) Lean body mass (kg) Mean±S.D p-value Mean±S.D p-value Mean±S.D p-value DXA-Inbody 0.6±2.3 0.012 0.3±1.7 0.038 0.4±1.7 0.014 DXA-X-scan 1.2±2.7 < 0.001 1.1±2.0 < 0.001 1.4±3.2 < 0.001 DXA: dual energy X-ray absortiometry. All differences are statistically significant in p-value <0.05 by paired t-test. 2. s³ DXA Inbody720 d w s³ ƒ 0.6± 2.3% (p =0.012), š DXA X-scan plusii d w s³ ƒ 1.2±2.7% (p<0.001) ùkûš, DXA Inbody720 d w s³ ƒ 0.3±1.7 kg (p =0.038), š DXA X-scan plus d w s³ ƒ 1.1±2.0 kg (p<0.001), DXA Inbody720 d w s³ ƒ 0.4±1.7 kg (p =0.014), š DXA X-scan plusii d w s³ ƒ 1.4±3.2 kg (p<0.001). Inbody720 X-scan plusii s³ DXA d w w ƒ (Table 2). 3. ü s³ ü CT BIA»» d ƒ ƒƒ w ƒ» w paired t-test ww. Inbody720 CT d w ü s³ 11.7±30.5 cm (p<0.001) w ƒ 2 ù, X- scan plusii CT d w ü s³ 2.0± 37.3 cm 2 (p=0.591), w ƒ (Table 3). 4. DXA BIA»» d w,, DXA Inbody720 d w (r = 0.922, p<0.001), (r = 0.932, p<0.001), (r = 0.985, p<0.001) w. w, DXA X-scan plusii d w (r = 0.897, p<0.001), (r = 0.910, p<0.001), (r = 0.943, p<0.001) w ƒ ùk û (Fig. 1). Table 3. Mean differences of the measured by Computer tomography, Inbody720 and X-scan plus II according to abdominal fat area. Visceral fat area (cm 2 ) Variable Mean±S.D p-value CT-Inbody 11.7±30.5 < 0.001 CT-X-scan 2.0±37.3 0.591 CT: Computer tomography. All differences are statistically significant in p-value <0.05 by paired t-test. 5. ü CT BIA»» d w ü ü CT Inbody720 d w ü (r = 0.599, p<0.001) w (Fig. 2A), ü CT X-scan plusii d w ü (r = 0.485, p<0.001) w (Fig. 2B). 6. ƒ BIA d Inbody720 X-scan plus d d DXA d d w ƒ w w ƒ ù(ƒƒ p<0.001, p<0.001), w (p = 0.31). ƒ BIA CT d ü m w (p =0.26). 7. DXA» BIA»» d w d e e DXA» d,, x w Inbody720 0.3±3.2%, 0.6±4.6 kg, 0.4±3.3 kg š, X-scan plusii ƒƒ 1.1±3.8%, 1.2±5.2 kg, 1.4±6.4 kg x w ƒ Inbody w (Fig. 3). 8. ü CT BIA»» d w ü e ü CT» ü d e ƒ» w Bland- Altman plots e w, Inbody720 x w 11.8±59.9 cm 2 š, X-scan plusii x w 2.0±73.2 cm 2 Inbody w (Fig. 4). š y y ù ƒw, 2005 ù 31.8%(û 35.2%, 28.3%) ùkû (19,20). ü vw ü, p ü

» w w» y 55 Fig. 1. Scatter plot of the body composition as measured by Dual energy X-ray absorptiometry, Inbody720 and X-scan plusii. Fig. 2. Scatter plot of the visceral fat area as measured by Computer tomography, Inbody720 and X-scan plusii.

56 ½ Á xá Á Fig. 3. Bland-Altman plot showing the mean value and the error allowance limits of the difference between body composotion by Dual energy X-ray absorptiometry and by Inbody720 and X-scan plusii. Fig. 4. Bland-Altman plot showing the mean value and the error allowance limits of the difference between visceral fat area measured by abdominal fat CT and by Inbody720 and X-scan plusii.

» w w» y 57 ew ü 2x, šx, y w w w š. DXA ƒ X- n k, X- d w z dw, ù,,, y w r k (21). CT d w» d w ü d w» w š (22,23).» w w p» w dw, w» w w w. m wù y 5 mx ƒ w ƒ v d wš, v ù w œ w w. e š ƒ wš»» rw ƒ, l, {p l, š. w InBody720 X-scan plus 1~1000 KHz q, 4 w BIA»» ü t d» z ƒ w. ƒ BIA d w,, DXA d w w ù, Inbody720 d ƒ X-scan plusii d w. w Inbody720 y ƒ X-scan plus II» j ƒ ù (r = 0.922 vs. r = 0.897), Inbody720 DXA», X-scan plus II (Isotope dilution)»» w ƒ ù ƒ. (17) Bland-Altman plots w DXA BIA e w, ƒƒ s³ x w ƒ 1.24±5.82%, 0.98±3.99 kg, 0.45± 4.23 kg šw š, DXA BIA ƒ j y. BIA»»,, d Inbody720(ƒƒ 0.3±3.2%, 0.6±4.6 kg, 0.4±3.3 kg) X-scan plusii(ƒƒ 1.1±3.8%, 1.2±5.2 kg, 1.4±6.4 kg) s³ x w ƒ. CT BIA ü d w (r = 0.652) (r = 0.24) ƒ, w (InBody720 r = 0.599, X-scan plusii r = 0.485) (24,25). ü w CT Inbody4.0 d w ü paired t-test w, w s³ ƒ(12.2±49.0 cm 2 ) ƒ ƒw ƒ f š šw (24). Inbody720 d ü CT d ü w ƒ ù( 11.7±30.5 cm 2, p<0.001), X-scan plusii d w ü CT d w w ƒ ( 2.0±73.2 cm 2, p = 0.591). ù X-scan plusii d w ü Inbody720 d w ü w s³ ƒ, w Inbody720 X-scan plusii w ƒ. w w w ü w û 100 w» yw w, BIA»ù, w š w w., DXA» ƒ» y w ƒ BIA»» d DXA d ù Inbody720 d X-scan plus II d w w ƒ (r = 0.922 vs. r = 0.897). BIA»» d ü CT d w ü ƒ û r, ü BIA w ƒ (r = 0.599 vs. r = 0.485). wz w w» BIA y w ƒ ƒ v w. š x 1. Welborn TA, Knuiman MW, Vu HT. Body mass index and alternatuive indices of obesity in relation to height, triceps skinfold and subsequent mortality: the Busselton health stuty. Int J Obes Relat Metab Disord 2000; 24: 108-115. 2. Strain GW, Zumoff B. The relationship of weight-height indicies of obesity to body fat content. J Am Coll Nutr 1992; 11: 715-718. 3. WHO. Report of a WHO Consultation on obesity: Preventing and managing, the global epidemic. Geneva: 1999. 4. Blackman MB. Obesity. Principle of ambulatory medicine. 4 th ed. 1994: 1102-1109. 5. Larsson B, Svardsudd K, Welin L, Wilhhenlmsen L, Bjorntorp P, Tibblin G. Abdominal adipose tissue distribution, obesity and risk of cardiovascular disease and death: a 13 year follow up of participants in the study of men born in 1913. Br Med J 1984; 288: 1401-1404. 6. Fuiioka S, Matsuzawa Y, Tokunaga K, Tarui S. Contribution of intra-abdominal fat accumulation to the impairment of glucose and lipid metabolism in human obesity. Metabolism 1987; 36 :54-59. 7. Nakajima T, Fujioka S, Tokunaga K, Matsuzawa Y, Tarui S.

58 ½ Á xá Á Correlation of intraabdominal fat accumulation and left ventricular performance in obesity. Am J Cardiol 1989; 64: 369-373. 8. Kanai H, Matsuzawa Y, Katoni K, Keno K, Kobatake T, Nagai Y. Close observation of intra-abdominal fat accumulation to hypertension in obese women. Hypertension in obese women. Hypertension 1990; 16 :484-490. 9. Ferranini E, Barrett EJ, Bevilacqua S, Defronzo RA. Effects of fatty acids on glucose production and utilization in man. J Clin Invest 1983; 72: 1737-1747. 10. Boden G. Fatty acids on insulin resistance. Diabetes Care 1996; 19: 394-395. 11. Svedberg J, Bjortorp P, Smith U, Lonroth P, Smith U, Lonroth P. Free-fatty acid inhibition of insulin binding, degradation and action in isolated rat hepatocyte. Diabetes 1990; 39: 570-574. 12. Bevilacqua S, Bonadonna R, Buzzigoli G, Boni C, Ciociaro D, Maccari F, Giorico MA, Ferranini E. Acute elevation of free fatty acid levels leads to hepatic insulin resistance in obese subjects. Metabolism 1990; 36: 570-574. 13. Lewis GP, Steiner G. Acute effects of insulin in the control of LVDV production in humans: implications for the insulinresistance state. Diabetes Care 1996; 19: 390-393. 14. Garg A. Insulin resistance in the pathogenesis of dyslipidemia. Diabetes Care 1996; 19: 387-389. 15. ½x, x.» w» x k. w wz 2002; 11: 389-397. 16., ½,, y, y, x. w d w. w wz 2002; 11: 150-157. 17.,, y», ½, w, ½. d» d sƒ. wz 2006; 6: 79-87. 18. Inoue S, Zimmet P, Caterson I, Chunming C, Ikeda Y, Khalid AK. The Asia-Pacific perspective:redefining obesity and its treatment. Melbourne: Health Communication; 2000. 19.. š. 2005. 20. Poston WC 2d, Foreyt JP, Borrell L, Haddock CK. Challenges in obesity management. South Med J 1998; 91: 710-720. 21. Prior BM, Cureton KJ, Modlesty CM, Evans EM, Sloniger MA, Ssunders M. In vivo validation of whole body composition estimates from dual-energy X-ray absorptiometry. J Appl Physiol 1997; 83: 623-630. 22. Nakamura T, Tokunaga K, Shimomura I. Contribution of visceral fat accumulation to the development of coronary artery in non-obese men. Atherosclerosis 1994; 107: 239-246. 23. Tokunaga K, Matsuzawa Y, Ishikawa K, Tarui S. A novel technique for the determination of body fat by computed tomography. Int J Obes 1983; 7: 437-445. 24., x, ½,.» InBody 4.0 x w ü x sƒ y. ƒ wz 2006; 27: 904-910. 25.,, y, y, ½.» w ful d w. d. wz. 2006; 7: 225-237.