title: Association between cystatin C and heart failure with preserved ejection fraction in elderly Chinese patients.
abstract: BACKGROUND
  Approximately 50 % of patients with heart failure have a preserved ejection fraction (HFpEF). Cystatin C has been reported to be associated with cardiovascular events. This study was carried out to investigate whether cystatin C is associated with cardiac function and cardiac diastolic properties in elderly Chinese HFpEF patients.
  
  
  METHODS
  A cross-sectional study of 381 elderly Chinese HFpEF patients (81 women, average age 82 ± 6 years) was conducted. Serum concentrations of cystatin C and the New York Heart Association (NYHA) classification were assessed and early (E) to late (A) transmitral flow velocity ratios (E/A ratio) were measured to assess cardiac diastolic properties.
  
  
  RESULTS
  Cystatin C levels, N‑terminal pro brain natriuretic peptide (NT-proBNP) levels and age were significantly correlated to the NYHA class (r = 0.605 P < 0.001, r = 0.333 P < 0.001 and r = 0.254 P < 0.001, respectively). Cystatin C levels, age and body mass index (BMI) were negatively correlated to the E/A ratio (r = -0.224 P = 0.005, r = -0.258 P = 0.001 and r = -0.258 P = 0.003, respectively). The patients with cystatin C concentrations below 1.3 mg/l had a higher E/A ratio compared to those with cystatin C concentrations higher than 1.3 mg/l. Cystatin C was also significantly associated with both the NYHA classification and the E/A ratio even after adjustment for the creatinine clearance rate (CCr).
  
  
  CONCLUSIONS
  Both cystatin C and NT-proBNP were found to be correlated to the NYHA classification. Independent of renal function, higher serum concentrations of cystatin C were associated with a worse NYHA classification and abnormal cardiac diastolic properties in elderly Chinese HFpEF patients.
authors.affiliation: Department of Geriatrics, Shanghai Jiaotong University affiliated Shanghai Sixth People's Hospital, 600 Yishan Road, 200233, Xuhui District, Shanghai, China.
authors.forename: C C
authors.initials: CC
authors.lastname: Xu
authors.affiliation: Department of Geriatrics, Shanghai Jiaotong University affiliated Shanghai Sixth People's Hospital, 600 Yishan Road, 200233, Xuhui District, Shanghai, China.
authors.forename: G X
authors.initials: GX
authors.lastname: Fu
authors.affiliation: Clinical Laboratory, Shanghai Jiaotong University affiliated Shanghai Sixth People's Hospital, Xuhui District, Shanghai, China.
authors.forename: Q Q
authors.initials: QQ
authors.lastname: Liu
authors.affiliation: Department of Geriatrics, Shanghai Jiaotong University affiliated Shanghai Sixth People's Hospital, 600 Yishan Road, 200233, Xuhui District, Shanghai, China. zhongyuansh60@163.com.
authors.forename: Y
authors.initials: Y
authors.lastname: Zhong
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity / Q000502:physiology; D015992:Body Mass Index; D002681:China; D000078331:Correlation of Data; D003430:Cross-Sectional Studies; D055316:Cystatin C / Q000097:blood*; D003971:Diastole / Q000502:physiology; D005260:Female; D006333:Heart Failure / Q000097:blood* / Q000453:epidemiology; D006801:Humans; D008297:Male; D008943:Mitral Valve / Q000503:physiopathology; D020097:Natriuretic Peptide, Brain / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D013318:Stroke Volume / Q000502:physiology*
chemical_list: D055316:Cystatin C; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain
keywords: Cystatin C; Diastolic properties; Elderly; Heart failure with preserved ejection fraction; NYHA classification