The following is a summary of “Prognostic Value of Creatinine versus Cystatin C-Based Estimation of Glomerular Filtration Rate for Mortality in Heart Failure,” published in the November 2023 issue of Cardiology by Roehm et al.
Researchers conducted a retrospective study to examine heart failure with reduced ejection fraction (HFrEF) data, comparing the prognostic power of creatinine and cystatin C-based estimated glomerular filtration rate (eGFR), alone and combined, to pinpoint the most accurate predictor of mortality.
They examined data from 310 participants in the Registry Evaluation of Vital Information for Ventricular Assist Devices in Ambulatory Life with baseline serum creatinine and cystatin C. The primary outcome was all-cause mortality. Cox models were adjusted for age, gender, race, diabetes mellitus, and NYHA class.
The results showed median eGFR by cr, cys, and cr-cys were 60, 58, and 60 ml/min/1.73m2, respectively. In the 2-year follow-up, 45 participants died, with eGFRcr and eGFRcys differing by -49 to 50 ml/min/1.73m2 within each patient. Worse survival was observed for estimates with baseline eGFR <60 ml/min/1.73m2. Lower baseline eGFRcr [HR 0.97, 95% CI (0.96-0.99), P =0.008, C 0.67], eGFRcys [HR 0.98 (0.97-0.99), P= 0.006, C= 0.68], and eGFRcr-cys [HR 0.98 (0.96-0.99), P= 0.004, C= 0.68] correlated with higher mortality. C-statistic comparisons revealed no significant difference in predictive ability: eGFRcr vs. eGFRcys, P=0.7; eGFRcr vs. eGFRcr-cys, P=0.9; eGFRcys vs. eGFRcr-cys, P=0.3).
They concluded that eGFR was linked to HFrEF death, but creatinine and cystatin C flunked as accurate predictors.