The Prognostic Importance of Cystatin C in Stable Heart Failure Without Chronic Kidney Disease

Background: Chronic heart failure represents the major cause of death and hospitalization in general population. Cystatin C has been identified as a novel biomarker that is sensitive in detecting early kidney dysfunction. Our aim was to investigate the prognostic importance of cystatin C in stable heart failure patients without renal insufficiency.Methods: We included 75 patients (50 males and 25 females, aged 67.6±10.6 years) who had been followed up with NYHA class 1-3 symptoms and who had an ejection fraction of <35% on echocardiography. Basal Cystatin C and other prognostic marker levels were measured. The variables of patients who died or had MACE during a median of 12 months period were compared with the patients who were free of MACE.Results: Multivariable analysis performed as the dependent variables revealed that, only cystatin C levels was determined as an independent risk factor for MACE rate [Hazard Ratio (HR) =32.56 (95% confidence interval (CI) ; 2.26-468.62), p=0.01)]. For mortality rate, the same analyses revealed an independent interaction with cystatin C, which could not reach significance [HR: 37.1 (95% CI; 0.94-1464), p=0.054)]. According to ROC analysis, cystatin C levels >1.45 mg/dL could predict mortality with 80% sensitivity and 63% specificity. Furthermore, cystatin C levels >1.45 mg/dL could predict MACE rate with %75 sensitivity and %81 specificity.Conclusions: Elevation of serum cystatin C is an independent prognostic marker for mortality and MACE rate in stable heart failure who had an ejection fraction of < 35% and a GFR of >60 ml/min/ 1.73m2.