title: Body Fat Analysis in Predialysis Chronic Kidney Disease: Multifrequency Bioimpedance Assay and Anthropometry Compared With Dual-Energy X-Ray Absorptiometry.
abstract: Body composition analysis is required for accurate assessment of nutritional status in patients with predialysis chronic kidney disease (CKD). The reference method for assessing body fat is dual-energy X-ray absorptiometry (DXA), but it is relatively expensive and often not available for widespread clinical use. There is only limited data on the utility of less expensive and easily available alternatives such as multifrequency bioimpedance assay (BIA) and skinfold thickness (SFT) measurements for assessing body fat in predialysis CKD. The study intends to assess the utility of BIA and SFT in measuring body fat compared to the reference method DXA in subjects with predialysis CKD.
  
  
  
  Body composition analysis was done in 50 subjects with predialysis CKD using multifrequency BIA, SFT, and DXA. The agreement between the body fat percentages measured by reference method DXA and BIA/SFT was assessed by paired t-test, intraclass correlation coefficients (ICCs), regression, and Bland-Altman plots.
  
  
  
  Percentage of body fat measured by BIA was higher compared to the measurements by DXA, but the difference was not significant (30.44 ± 9.34 vs. 28.62 ± 9.00; P = .071). The ICC between DXA and BIA was 0.822 (confidence interval: 0.688, 0.899; P = .000). The mean values of body fat percentages measured by anthropometry (SFT) was considerably lower when compared to DXA (23.62 ± 8.18 vs. 28.62 ± 9.00; P = .000). The ICC between DXA and SFT was .851 (confidence interval: 0.739, 0.915; P = .000). Bland-Altman plots showed that BIA overestimated body fat by a mean of 1.8% (standard deviation, 6.98), whereas SFT underestimated body fat by 5% (standard deviation, 4.01). Regression plots showed a better agreement between SFT and DXA (R(2) = .79) than BIA (R(2) = .50). Overall, SFT showed better agreement with the DXA. Body mass index (BMI) showed a moderate positive correlation with body fat measured by DXA whereas serum albumin failed to show good correlation.
  
  
  
  SFT showed relatively better agreement with the reference method DXA, compared to BIA. SFT can be used as a tool for assessing nutritional status in predialysis patients with CKD.
authors.affiliation: Department of Nephrology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry 605006, India.
authors.forename: Jayasurya
authors.initials: J
authors.lastname: Ravindranath
authors.affiliation: Department of Nephrology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry 605006, India. Electronic address: priyamvadaps@gmail.com.
authors.forename: Priyamvada P Sivan
authors.initials: PP
authors.lastname: Pillai
authors.affiliation: Department of Nephrology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry 605006, India.
authors.forename: Sreejith
authors.initials: S
authors.lastname: Parameswaran
authors.affiliation: Department of Endocrinology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry 605006, India.
authors.forename: Sadish Kumar
authors.initials: SK
authors.lastname: Kamalanathan
authors.affiliation: Department of Physiology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry 605006, India.
authors.forename: Gopal Krushna
authors.initials: GK
authors.lastname: Pal
mesh_terms: D015502:Absorptiometry, Photon; D000273:Adipose Tissue; D000886:Anthropometry; D001823:Body Composition; D015992:Body Mass Index; D017097:Electric Impedance; D006801:Humans; D051436:Renal Insufficiency, Chronic