ABSTRACT
Conventional hemodialysis (HD) is the most common treatment modality used for renal replacement therapy. The concept of HD is based on the diffusion of solutes across a semipermeable membrane. Hemofiltration (HF) is based on convective transport of solutes; hemodiafiltration (HDF) is based on combined convective and diffusive therapies. Data about survival benefit of on-line HDF (OL-HDF) over high-flux HD (HF-HD) is conflicting. We conducted this study to investigate if there is a survival difference between the two treatment modalities. This study is a retrospective, single-center study in which 78 patients were screened; 18 were excluded and 60 patients were analyzed. The study patients were aged 47.5 ± 20.7 years, 33 patients (55%) were on HF-HD, and 27 patients (45%) were on OL-HDF. A total of 24 patients (40%) of both groups were diabetic and, the mean duration on dialysis was 43.5 ±21.3 months in the HF-HD group and 41.2 ± 22.0 months in the OL-HDF group. The mean substitution volume for OL-HDF was 22.3 ± 2.5 L. Survival was 73% [95%, confidence interval (CI) 60-84] in the HF-HD group and 65% (95%, CI 54-75) in the OL-HDF group by the end of the study period. The unadjusted hazard ratio (HR) with 95% CI comparing HF-HD to high-volume postdilution OL-HDF was 0.78 (0.10-5.6; P = 0.810). Kaplan-Meier analysis for patient survival over five years showed no significant difference between the two modalities. Prospective controlled trials with a larger number of patients will be needed to assess the long-term clinical outcome of postdilution OL-HDF over HF-HD.
