Effects of high-efficiency postdilution online hemodiafiltration and high-flux hemodialysis on serum phosphorus and cardiac structure and function in patients with end-stage renal disease.

Background/aim: Cardiovascular disease is the leading cause of mortality in patients with chronic kidney disease and has a strong association with hyperphosphatemia. Dialysis is the major treatment tool for attaining serum phosphorus control. Phosphorus removal can be increased with hemodiafiltration. We compared the effect of hemodiafiltration and hemodialysis on serum phosphorus and phosphorus removal and changes in cardiovascular variables in a short-term follow-up.

Methods: Adult patients with end-stage renal disease were randomized to receive hemodialysis or hemodiafiltration for 3 months. Clinical and biochemical variables were recorded monthly. Cardiac resonance was done at randomization and at the end of follow-up.

Results: A total of 24 patients were studied (10 in hemodialysis and 14 in hemodiafiltration) with a mean age of 34.7 ± 11.4 years. The two groups did not differ as for age and blood pressure control at baseline. Phosphorus removal was higher (1,099 ± 239 in hemodiafiltration vs. 864 ± 366 mmol/session in hemodialysis, p < 0.05) and serum phosphorus was lower in the hemodiafiltration group at the end of follow-up (3.4 ± 0.8 in hemodiafiltration vs. 4.5 ± 1.6 mg/dl in hemodialysis, p < 0.05). We found a significant increase in ejection fraction only in the hemodiafiltration group. There was a trend to smaller increase in myocardial mass and a decrease in left ventricular end-diastolic volume only in the hemodiafiltration group. The changes in cardiac variables were significantly associated with changes in serum phosphorus levels.

Conclusion: Hemodiafiltration was associated with better control of serum phosphorus and improvement in left ventricular ejection fraction, compared with hemodialysis.