title: Cystatin-C and mortality in elderly persons with heart failure.
abstract: OBJECTIVE
  We sought to evaluate cystatin-C, a novel measure of renal function, as a predictor of mortality in elderly persons with heart failure (HF) and to compare it with creatinine.
  
  
  BACKGROUND
  Renal function is an important prognostic factor in patients with HF, but creatinine levels, which partly reflect muscle mass, may be insensitive for detecting renal insufficiency.
  
  
  METHODS
  A total of 279 Cardiovascular Health Study participants with prevalent HF and measures of serum cystatin-C and creatinine were followed for mortality outcomes over a median of 6.5 years.
  
  
  RESULTS
  Median creatinine and cystatin-C levels were 1.05 mg/dl and 1.26 mg/l. Each standard deviation increase in cystatin-C (0.35 mg/l) was associated with a 31% greater adjusted mortality risk (95% confidence interval [CI] 20% to 43%, p < 0.001), whereas each standard deviation increase in creatinine (0.39 mg/dl) was associated with a 17% greater adjusted mortality risk (95% CI 1% to 36%, p = 0.04). When both measures were combined in a single adjusted model, cystatin-C remained associated with elevated mortality risk (hazard ratio 1.60, 95% CI 1.32 to 1.94), whereas creatinine levels appeared associated with lower risk (hazard ratio 0.73, 95% CI 0.57 to 0.95).
  
  
  CONCLUSIONS
  Cystatin-C is a stronger predictor of mortality than creatinine in elderly persons with HF. If confirmed in future studies, this new marker of renal function could improve risk stratification in patients with HF.
authors.affiliation: General Internal Medicine Section, Veterans Affairs Medical Center, 4150 Clement Street, University of California-San Francisco, San Francisco, CA 94121, USA. shlip@itsa.ucsf.edu
authors.forename: Michael G
authors.initials: MG
authors.lastname: Shlipak
authors.forename: Ronit
authors.initials: R
authors.lastname: Katz
authors.forename: Linda F
authors.initials: LF
authors.lastname: Fried
authors.forename: Nancy Swords
authors.initials: NS
authors.lastname: Jenny
authors.forename: Catherine  O
authors.initials: C
authors.lastname: Stehman-Breen
authors.forename: Anne B
authors.initials: AB
authors.lastname: Newman
authors.forename: David
authors.initials: D
authors.lastname: Siscovick
authors.forename: Bruce M
authors.initials: BM
authors.lastname: Psaty
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Sarnak
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D003404:Creatinine / Q000097:blood; D055316:Cystatin C; D015891:Cystatins / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006333:Heart Failure / Q000097:blood* / Q000401:mortality*; D006801:Humans; D008297:Male; D010865:Pilot Projects; D011237:Predictive Value of Tests; D018570:Risk Assessment; D016019:Survival Analysis
chemical_list: C525030:CST3 protein, human; D055316:Cystatin C; D015891:Cystatins; D003404:Creatinine