Creatinine Clearance Measurement with Bioelectrical Impedance Analysis in Heart Failure Patients: Comparison with Estimated-Creatinine Clearance Formulas.

Background: Kidney disease is common in patients with heart failure (HF). The Donadio equation combines plasma creatinine and bioimpedance vector analysis (BIVA) to estimate creatinine clearance. This study aimed to compare the Donadio formula to the Cockcroft-Gault (CG), Modification of Diet in Renal Disease Study (MDRD-4), and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations in patients with HF.

Methods: We analysed data from 900 patients (mean age: 76 ± 10 years) with HF. All of them underwent clinical, laboratory, BIVA, and echocardiographic evaluations.

Results: Donadio equation overestimated eGFR as compared to CG and CKD-EPI formulas (+6.8 and +12 mL/min/1.73 m2, respectively) while computing similar results to MDRD-4 (overestimation: +0.1 mL/min/1.73 m2). According to the different formulas, the prevalence of renal insufficiency (eGFR< 30 ml/min/1.73 m2) in relation to the different formulas was as follows: 24% with Donadio, 21% with CG, 13% with MDRD-4, and 23% with CKD-EPI formulas. All the equations demonstrated a high precision rate (r>0.8 for all). There was a "good" agreement between the Donadio and CG/MDRD-4 formulas and "fair" with the CDK-EPI formula. The Donadio equation showed a high accuracy in predicting severe renal dysfunction (eGFR< 30 mL/min/1.73 m2) in patients with HF (AUC > 0.9), showing comparable performances to CG.

Conclusion: The Donadio formula provided an estimation of GFR comparable to MDRD-4 in HF patients, independently from acute or chronic HF conditions. The use of BIVA in HF patients may be adopted both for HF management and for evaluating kidney function.