title: Prognostic value of cystatin C on admission in heart failure with preserved ejection fraction.
abstract: BACKGROUND
  Cystatin C has emerged as a new biomarker of renal function that has been found to predict adverse cardiovascular outcomes, especially heart failure (HF). Evidence of the usefulness of cystatin C in patients with heart failure with preserved ejection fraction (HFPEF) remains sparse. It is hypothesized that serum cystatin C levels in HFPEF has prognostic value.
  
  
  RESULTS
  Cystatin C, urea nitrogen, creatinine, and N-terminal proBNP-type natriuretic peptide levels were measured on admission in 218 consecutive patients with HF and left ventricular ejection fraction >45%, as measured by Doppler echocardiography. The primary end point was all-cause mortality and/or readmission at 1 year. We determined the adjusted hazard ratio (HR) by Cox regression model. During the 1-year follow-up period, 70 patients (32.2%) died, and 126 patients (57.8%) died and/or required rehospitalization. Serum cystatin C levels by quartiles were associated with increased risk for adverse events. Kaplan-Meier survival curves showed significantly increased primary end point with each quartile of cystatin C (log rank <0.001). Patients in the highest quartile of cystatin C level were at increased adjusted risk for the primary end point (HR 3.40; 95% confidence interval [CI] 1.86-6.21; P < .0001) and all-cause mortality (HR 8.14; 95% CI 1.21-23.26; P < .01). Furthermore, high serum cystatin C levels were also associated with poor prognosis despite normal or mildly reduced renal function.
  
  
  CONCLUSIONS
  Serum cystatin C level on admission in patients with HFPEF is a strong and independent predictor of an unfavorable outcome. This relationship remains in patients without advanced renal dysfunction.
authors.affiliation: Department of Internal Medicine, Hospital Juan Ramón Jiménez, Huelva, Spain. fjcarrascos@telefonica.net
authors.forename: Francisco Javier
authors.initials: FJ
authors.lastname: Carrasco-Sánchez
authors.forename: Luis
authors.initials: L
authors.lastname: Galisteo-Almeda
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Páez-Rubio
authors.forename: Francisco Javier
authors.initials: FJ
authors.lastname: Martínez-Marcos
authors.forename: Crescencio
authors.initials: C
authors.lastname: Camacho-Vázquez
authors.forename: Carlos
authors.initials: C
authors.lastname: Ruiz-Frutos
authors.forename: Emilio
authors.initials: E
authors.lastname: Pujol-De La Llave
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D055316:Cystatin C / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000097:blood* / Q000175:diagnosis* / Q000401:mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D010343:Patient Admission / Q000639:trends; D010359:Patient Readmission / Q000639:trends; D011379:Prognosis; D011446:Prospective Studies; D013318:Stroke Volume / Q000502:physiology*
chemical_list: D015415:Biomarkers; D055316:Cystatin C