Cystatin C as a predictor for outcomes in patients with negligible renal function

Background: High serum cystatin C (CysC) has been associated with clinical risks independently of the glomerular filtration rate (GFR). This study aims to investigate the predictive power of CysC in patients with a negligible GFR. Methods: Patients on chronic hemodialysis or peritoneal dialysis were enrolled for measurement of CysC levels and were followed up for one year. A daily urine amount <100 ml was considered negligible residual renal function (RRF). Results: CysC results were available in 183 dialysis patients. Of these, 131 patients had a negligible RRF. The multivariate Cox proportional hazards model showed that CysC was an independent predictor of fatal and nonfatal cardiovascular and infection events in all dialysis patients and in dialysis patients with a negligible RRF. Conclusion: CysC maintained its predictive power for adverse outcomes in patients with no meaningful GFR, indicating that the prognostic value of CysC is independent of the GFR.