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Abstract: PO1177

High-Volume Hemodiafiltration Reduces Pre-Dialysis Beta-2 Microglobulin Concentration Compared with High-Flux Hemodialysis: A Post Hoc Analysis of the HDFit Trial

Session Information

Category: Dialysis

  • 701 Dialysis: Hemodialysis and Frequent Dialysis


  • Guedes, Murilo Henrique, Pontificia Universidade Catolica do Parana, Curitiba, PR, Brazil
  • Larkin, John W., Fresenius Medical Care North America, Waltham, Massachusetts, United States
  • Almeida, Ana clara Simões flórido, Pontificia Universidade Catolica do Parana, Curitiba, PR, Brazil
  • Santos, Ana Claudia, Pontificia Universidade Catolica do Parana, Curitiba, PR, Brazil
  • Barra, Ana Beatriz Lesqueves, Fresenius Medical Care Brazil, Rio de Janeiro, Rio de Janeiro, Brazil
  • Poli de Figueiredo, Carlos Eduardo, Pontificia Universidade Catolica do Rio Grande do Sul, Porto Alegre, RS, Brazil
  • Canziani, Maria Eugenia F., Clínica de Diálise Ingá, Rio de Janeiro, Brazil
  • Moreno-Amaral, Andrea Novais, Pontificia Universidade Catolica do Parana, Curitiba, PR, Brazil
  • Raimann, Jochen G., Renal Research Institute, New York, New York, United States
  • Kotanko, Peter, Renal Research Institute, New York, New York, United States
  • Canaud, Bernard J., Fresenius Medical Care AG und Co KGaA, Bad Homburg, Hessen, Germany
  • Pecoits-Filho, Roberto, Pontificia Universidade Catolica do Parana, Curitiba, PR, Brazil

High-volume hemodiafiltration (HDF) is a diffusive-convective modality that provides higher clearance of middle-size uremic toxins, such as beta-2 microglobulin (β2M), compared to predominantly diffusive high-flux hemodialysis (HD). Previous studies have shown HDF may reduce circulating pre-dialysis concentrations of β2M compared to low-flux HD. We studied to which extent HDF reduces pre-dialysis β2M concentrations compared to high-flux HD.


HDFit randomized patients with a permanent vascular access time on HD between 3 and 24 months to either high flux HD or high volume HDF (convective volume (CV) target of 22L/session) / treatment). Patients were followed for 6 months. Measurements of circulating pre-dialysis β2M levels were made at baseline, 3 and 6 months during mid-week session. Linear mixed effects models were used to estimate the mean difference (95% confidence interval (CI)) in β2M levels between HDF and HD.


A total of 195 patients (mean age 53±15 years, albumin 4±0.4 g/dL) were randomized (HDF n=97, HD n=98). Patient characteristics were balanced across intervention groups. Median treatment time was 235 min in both groups. Monthly mean CV ranged from 27.1 to 27.5L/treatment; the target CV was achieved in 96 out of 97 patients.Compared to HDF, in the HD arm monthly mean pre-dialysis β2M levels were 1.57 mg/L (95% CI 0.02 to 3.12) higher. In other words, HDF reduced mean circulating β2M levels over time compared to HD. (Figure).


In this post-hoc analysis of the HDFit trial, we describe for the first time that high-volume HDF sustainably reduces pre-dialysis β2M concentration compared to high-flux HD. High convective volume was easily achieved with online HDF. Our findings suggest that HDF can be readily implemented and that this treatment modality yields a sustained higher control of middle-size uremic toxins.


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