title: Bioelectrical impedance analysis and skinfold thickness sum in assessing body fat mass of renal dialysis patients.
abstract: OBJECTIVE
  In chronic renal failure patients under hemodialysis (HD) treatment, the availability of simple, safe, and effective tools to assess body composition enables evaluation of body composition accurately, in spite of changes in body fluids that occur in dialysis therapy, thus contributing to planning and monitoring of nutritional treatment. We evaluated the performance of bioelectrical impedance analysis (BIA) and the skinfold thickness sum (SKF) to assess fat mass (FM) in chronic renal failure patients before (BHD) and after (AHD) HD, using air displacement plethysmography (ADP) as the standard method.
  
  
  METHODS
  This single-center cross-sectional trial involved comparing the FM of 60 HD patients estimated BHD and AHD by BIA (multifrequential; 29 women, 31 men) and by SKF with those estimated by the reference method, ADP. Body fat-free mass (FFM) was also obtained by subtracting the total body fat from the individual total weight.
  
  
  RESULTS
  Mean estimated FM (kg [%]) observed by ADP BHD was 17.95 ± 0.99 kg (30.11% ± 1.30%), with a 95% confidence interval (CI) of 16.00 to 19.90 (27.56 to 32.66); mean estimated FM observed AHD was 17.92 ± 1.11 kg (30.04% ± 1.40%), with a 95% CI of 15.74 to 20.10 (27.28 to 32.79). Neither study period showed a difference in FM and FFM (for both kg and %) estimates by the SKF method when compared with ADP; however, the BIA underestimated the FM and overestimated the FFM (for both kg and %) when compared with ADP.
  
  
  CONCLUSIONS
  The SKF, but not the BIA, method showed results similar to ADP and can be considered adequate for FM evaluation in HD patients.
authors.affiliation: Digestive Surgery Division, Department of Gastroenterology, University of Sao Paulo School of Medicine, Sao Paulo, Brazil.
authors.forename: Natália Cristina Lima
authors.initials: NC
authors.lastname: Rodrigues
authors.forename: Priscila Campos
authors.initials: PC
authors.lastname: Sala
authors.forename: Lilian Mika
authors.initials: LM
authors.lastname: Horie
authors.forename: Maria Carolina Gonçalves
authors.initials: MC
authors.lastname: Dias
authors.forename: Raquel Susana Matos de Miranda
authors.initials: RS
authors.lastname: Torrinhas
authors.forename: João Egídio
authors.initials: JE
authors.lastname: Romão
authors.forename: Ivan
authors.initials: I
authors.lastname: Cecconello
authors.forename: Dan Linetzky
authors.initials: DL
authors.lastname: Waitzberg
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D000328:Adult; D001823:Body Composition; D003430:Cross-Sectional Studies; D017097:Electric Impedance; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010991:Plethysmography / Q000379:methods; D006435:Renal Dialysis; D012885:Skinfold Thickness