Impact of Hemodiafiltration and Hemodialysis on FGF-23 Levels and Cardiovascular Calcification in End-Stage Renal Disease

Background: End-stage renal disease (ESRD) often leads to systemic complications, including vascular calcification, which significantly increases cardiovascular (CV) risk. Fibroblast growth factor 23 (FGF-23), an endocrine regulator of phosphate metabolism, has been implicated in the development of vascular calcification, though its precise role remains unclear. Hemodiafiltration (HDF) is an advanced dialysis modality that may influence FGF-23 levels and, consequently, CV risk. This study aims to explore the relationship between FGF-23, dialysis modality, and vascular calcification in ESRD patients. Methods: A cross-sectional study was conducted on 50 ESRD patients (25 on hemodialysis and 25 on hemodiafiltration) at Ain Shams University Specialized Hospitals, Egypt. FGF-23 levels were measured pre- and post-dialysis, and cardiovascular calcification was assessed using echocardiography and carotid duplex ultrasound. Laboratory parameters and inflammatory markers were also recorded. Statistical analysis was performed using SPSS version 26. Results: Pre-dialysis FGF-23 levels were significantly lower in the HDF group compared to the HD group (p = 0.015). The reduction ratio of FGF-23 was significantly higher in HDF patients (p < 0.001). Both groups exhibited similar levels of arterial plaque, but the HD group had significantly greater carotid intima-media thickness (IMT) (p = 0.035), suggesting an increased risk of cardiovascular complications. Post-treatment FGF-23 levels correlated with serum calcium, phosphorus, parathyroid hormone (PTH), and C-reactive protein (CRP), with stronger correlations observed in the HDF group. Conclusion: Hemodiafiltration is more effective than hemodialysis in reducing FGF-23 levels, potentially offering an advantage in controlling vascular calcification and reducing cardiovascular risk in ESRD patients. Despite similar plaque burdens, HDF patients demonstrated less carotid intima-media thickening, suggesting a better overall cardiovascular profile.