title: Relative contributions of inflammation and inadequate protein intake to hypoalbuminemia in patients on maintenance hemodialysis.
abstract: OBJECTIVE
  Serum albumin is one of the strongest mortality predictors in maintenance hemodialysis (MHD) patients. Yet, the degree to which serum albumin represents dietary protein intake or an inflammatory state, among others, is not clear. We hypothesize that these inadequate protein intake and inflammation contribute somewhat equally to hypoalbuminemia.
  
  
  METHODS
  In a cross-sectional analysis, we examined correlates of low serum albumin, <3.8 g/dL, in 812 MHD patients in whom interleukin-6 (IL-6) and normalized protein nitrogen appearance (nPNA), also known as normalized protein catabolic rate (nPCR), were also measured. Logistic regression estimated odds ratios were employed, and spline models were plotted to examine the likelihood of relatively low serum albumin <3.8 g/dL.
  
  
  RESULTS
  Mean age (±SD) of patients was 54 ± 15 years; 53 % of patients were men, 50 % Hispanic, 31 % African-American, and 55 % diabetic. The mean dialysis vintage was 31 ± 34 months (median: 19, inter-quartile range: 7-44 months). The baseline serum albumin, averaged over a 3-month period (mean ± SD), was 3.88 ± 0.38 g/mL. The unadjusted correlation coefficients of l IL-6 and nPNA with serum albumin were -0.36 and +0.20, respectively (p < 0.001 for each comparison). The likelihood for an albumin <3.8 gr/dL increased linearly with decreasing nPNA and rising serum IL-6. This trend was steeper with increasing serum IL-6 up to a concentration of 30 ng/mL.
  
  
  CONCLUSIONS
  Both low protein intakes and a high state of inflammation are associated with low serum albumin in MHD patients.
authors.affiliation: Harold Simmons Center for Kidney Disease Research and Epidemiology, Torrance, CA, USA.
authors.forename: Youngmee
authors.initials: Y
authors.lastname: Kim
authors.forename: Miklos Z
authors.initials: MZ
authors.lastname: Molnar
authors.forename: Manoch
authors.initials: M
authors.lastname: Rattanasompattikul
authors.forename: Parta
authors.initials: P
authors.lastname: Hatamizadeh
authors.forename: Debbie
authors.initials: D
authors.lastname: Benner
authors.forename: Joel D
authors.initials: JD
authors.lastname: Kopple
authors.forename: Csaba P
authors.initials: CP
authors.lastname: Kovesdy
authors.forename: Kamyar
authors.initials: K
authors.lastname: Kalantar-Zadeh
mesh_terms: D000328:Adult; D000368:Aged; D002097:C-Reactive Protein / Q000378:metabolism; D003404:Creatinine / Q000097:blood; D003430:Cross-Sectional Studies; D004044:Dietary Proteins / Q000378:metabolism*; D005260:Female; D006801:Humans; D034141:Hypoalbuminemia / Q000097:blood / Q000209:etiology*; D007249:Inflammation / Q000097:blood / Q000150:complications*; D015850:Interleukin-6 / Q000097:blood; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011488:Protein Deficiency / Q000097:blood / Q000150:complications*; D006435:Renal Dialysis; D051436:Renal Insufficiency, Chronic / Q000097:blood / Q000628:therapy; D012709:Serum Albumin / Q000378:metabolism
chemical_list: D004044:Dietary Proteins; D015850:Interleukin-6; D012709:Serum Albumin; D002097:C-Reactive Protein; D003404:Creatinine