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Kidney Week

Abstract: FR-PO900

Hemodiafiltration and Mortality: Data from the Real World

Session Information

Category: Dialysis

  • 607 Dialysis: Epidemiology, Outcomes, Clinical Trials - Non-Cardiovascular


  • Fernandes, Ana, Centro Hospitalar Setubal, Setubal, Portugal

Mortality remains high for hemodialysis (HD) patients and no single intervention has shown to decrease mortality. Online hemodiafiltration (HDF) is a promising technique, but randomized trials have shown inconsistent results.


We conducted a cohort study including all incident patients that started dialysis in 40 randomly selected units over a two-year period, and these patients were followed for at least 5 years, or until death or loss to follow up whichever occurred first. A descriptive statistic was used to characterize the population. To analyse time to mortality we used the Cox’s Proportional Hazard model to evaluate the covariates that may modify the outcome. Covariates included in the model were comorbidities and vascular access type.


1,229 patients were included. Mean age was 65.2±15.5 years, 40.4% were male. Diabetes was the most frequent cause of CKD. At baseline, 23% had coronary artery disease (CAD), 43.7% had diabetes (DM), 31.3% had cerebrovascular disease (CBD) and 2.4% peripheral artery disease (PAD). Vascular access at the beginning of dialysis was a catheter in 45.9% of the patients, an arteriovenous fistula in 49.7% and a graft in 4.4%. Eight per cent of the patients were undergoing low flux HD, 66.5% high flux HD and 22% HDF.
Three per cent of the patients were taking a calcimimetic, 37,9% were receiving a vitamin D analogue and the most common phosphate binding utilized was calcium carbonate. Median time of follow up was 48 months (Interquartile range 22-64)
Univariate analysis showed that CAD (hazard ratio [HR] 1.89; 95%CI 1.54-2.32), DM (HR 1.32; 95%CI; 1.09-1.60), and PAD (HR 2.05; 95%CI 1.22-3.44) were associated with increased mortality.
In multivariate analysis only CAD was associated with an increased risk of death (HR 2.00; 95%CI 1.61-2.46).
Hemodiafiltration, as compared with low flux dialysis, was associated with a decreased mortality (HR 0.34, 95%CI 0.49-0.89). There was no difference in the risk of death between low-flux and high-flux hemodialysis (HR 1.19; 95%CI 0.92-1.55). Median survival time was not yet reached but it was longer in the hemodiafiltration group. (p< 0,0001)


This study suggests that HDF, as compared with low-flux dialysis, may reduce the risk of mortality. The magnitude of the effect size is possibly overestimated by the observational nature of study.