ASN's Mission

To create a world without kidney diseases, the ASN Alliance for Kidney Health elevates care by educating and informing, driving breakthroughs and innovation, and advocating for policies that create transformative changes in kidney medicine throughout the world.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005

email@asn-online.org

202-640-4660

The Latest on X

Kidney Week

Abstract: PUB096

Weekly Trends in Phosphate Levels During Hemodiafiltration

Session Information

Category: Dialysis

  • 801 Dialysis: Hemodialysis and Frequent Dialysis

Authors

  • Wagner, Carolina Steller, Nefrostar Kidney Care, Sao Paulo, Brazil
  • Resende, Larissa, Nefrostar Kidney Care, Sao Paulo, Brazil
  • Batista, Lucileide, Nefrostar Kidney Care, Sao Paulo, Brazil
  • Quilelli, Amanda L, Nefrostar Kidney Care, Sao Paulo, Brazil
  • Kojima, Christiane, Nefrostar Kidney Care, Sao Paulo, Brazil
  • Rocha, Érica Pires da, Nefrostar Kidney Care, Sao Paulo, Brazil
  • Costa, Daniel Monte, Nefrostar Kidney Care, Sao Paulo, Brazil
  • Rosa, Maria G., Nefrostar Kidney Care, Sao Paulo, Brazil
  • Magalhães, Andréa Olivares, Nefrostar Kidney Care, Sao Paulo, Brazil
  • Cuppari, Lilian, Nefrostar Kidney Care, Sao Paulo, Brazil
  • Elias, Rosilene M., Nefrostar Kidney Care, Sao Paulo, Brazil
Background

Phosphate (P) levels control in patients on dialysis remains a challenge. Hemodiafiltration (HDF) appears to improve P levels, though the literature is limited regarding the evaluation of hyperphosphatemia throughout the week. We hypothesized that P levels would improve during a HDF week, with a reduction in prevalence toward the last sessions.

Methods

This cross-sectional, multicenter study aimed to evaluate P levels before dialysis, after 1 hour, and at the end of the procedure in patients on maintenance HDF. Data from all consecutive HDF sessions over one week were included. We have compared P levels according to dialysis shift, frequency (3 vs. 4-6 times per week), and duration. Hyperphosphatemia was defined as pre HDF P levels > 5.5 mg/dL.

Results

A total of 79 patients (60.8% male, 44% on conventional, 49.4% on short-daily and 6.3% on long nocturnal HDF) were included in the study. P levels measured before HDF, after 1 hour, and at the end of the procedure did not differ significantly across dialysis shifts, frequency, or session duration (p > 0.05 for all comparisons). A significant reduction in P levels was observed, with decreases of up to 2.5 mg/dL after 1 hour and 2.8 mg/dL at the end of the procedure across all sessions throughout the week. Pre-dialysis P levels decreased from the first to the last session of the week in patients undergoing 3, 5, and 6 sessions of HDF/week. Among the first three HDF sessions, 27.6% of patients exhibited persistent hyperphosphatemia. This group had significantly higher P levels (p<0.001), urea (p=0.014), and parathyroid hormone (PTH) levels (p=0.034) before the first HDF session of the week compared to patients without hyperphosphatemia, who represented 51.3% of the cases. Additionally, 14.5% of patients showed improvement in hyperphosphatemia, which occurred mostly in the second session (72.7%).

Conclusion

Hyperphosphatemia remains a challenging issue for patients undergoing HDF. The characteristics of the patients, as well as the timing of P level assessments throughout the week, significantly influence the prevalence of hyperphosphatemia. These findings highlight the need for a standardized approach in assessing hyperphosphatemia in dialysis patients to facilitate comparisons across populations and studies.

Digital Object Identifier (DOI)