Abstract 3616: Relation of Cystatin C to Natriuretic Peptide, Creatinine Clearance, and Prognosis in Patients with Chronic Systolic Heart Failure
Background: Cystatin C is a new marker that has been implicated as a more refined predictor of renal function and an independent prognostic marker in chronic heart failure. We sought to better understand the relationship of Cystatin C with disease severity as measured by plasma NT-proBNP and estimated creatinine clearance, and their relative prognostic values.
Methods: We identified 138 consecutive subjects with chronic, stable, systolic heart failure (NYHA II-IV, LVEF ≤35%) from the ADEPT study and measured plasma levels of cystatin C and NT-proBNP. Creatinine clearance (CrCl) was estimated by the Cockcroft-Gault equation. We prospectively examined long-term clinical outcomes (death, transplant, and heart failure hospitalizations) of these subjects.
Results: Plasma cystatin C levels increased with worsening creatinine clearance (Spearman’s r =−0.49, p<0.0001), higher plasma NT-proBNP (r = 0.57, p<0.0001). When considering the subgroup of patients with preserved renal function (CrCl≥60 mL/min), NT-proBNP was the only predictor of elevated cystatin C levels in multivariable analysis (standardized β=0.33, p<0.0001). Upon adjustment for CrCl, increasing cystatin C quartiles remained a significant risk factor for mortality (RR: 2.60, 95% CI: 1.51 – 4.86, p<0.001, see Figure⇓), and independent of NT-proBNP levels.
Conclusion: In our study cohort of patients with chronic systolic heart failure, plasma cystatin C correlates with plasma NT-proBNP levels, and remains an independent prognostic marker after adjusting for creatinine clearance and plasma NT-proBNP levels, suggesting it may be a unique marker of prognosis in heart failure.