NT-proBNP as a Predictor of Chronic Kidney Disease Progression

Background: N-terminal pro–B-type natriuretic peptide (NT-proBNP) is a cardiac biomarker with emerging relevance in chronic kidney disease (CKD). While elevated NT-proBNP levels are commonly attributed to cardiac dysfunction, recent evidence suggests they may also reflect renal pathology and predict CKD progression. This single-center study aimed to evaluate the predictive role of NT-proBNP in CKD progression independent of structural heart disease.

Methods: We enrolled 24 patients with stage 3–5 CKD, all with normal cardiac function confirmed by echocardiography (normal ejection fraction and left ventricular indices). Baseline NT-proBNP and comprehensive metabolic parameters (renal function, lipids, glycemic markers, inflammatory markers, nutritional indicators) were measured and repeated at 24 weeks. Changes in NT-proBNP were correlated with changes in renal function (creatinine clearance) and other variables. Statistical significance was set at p<0.05. We also considered advanced analyses (ROC curve and multivariate regression) to further assess NT-proBNP’s prognostic performance.

Results: NT-proBNP levels rose significantly over 24 weeks (p<0.001) as renal function declined (creatinine clearance decreased, p<0.001). There was an inverse correlation between the change in NT-proBNP and change in creatinine clearance (r = –0.437, p<0.05), even after excluding patients with heart failure or other cardiac abnormalities. Baseline NT-proBNP correlated negatively with serum albumin and total protein (r = –0.525 and –0.414, respectively), and these correlations persisted at follow-up (r = –0.577 and –0.483; p<0.01). Subgroup analysis showed the NT-proBNP–renal function relationship was more pronounced in diabetic CKD patients (r = –0.638, p<0.05) than in non-diabetics. NT-proBNP changes were not significantly associated with body mass index, blood pressure, lipid profile, or HbA1c. High-sensitivity C-reactive protein (hs-CRP) increased during follow-up, but its change did not correlate with NT-proBNP change.

Conclusion: NT-proBNP levels increased in tandem with CKD progression, suggesting NT-proBNP is a promising marker for monitoring renal deterioration independent of heart function. Its strong association with nutritional status (albumin/protein levels) implies a multifactorial biomarker role. Larger prospective studies and advanced statistical analyses (e.g., threshold determination via ROC, multivariate models) are warranted to validate NT-proBNP’s prognostic value and to integrate it into clinical decision-making for CKD.