New epidemiological cohort study supports recent ESHOL data
The epidemiological cohort study compared the survival of incident patients on three different treatment modalities: high-flux hemodialysis (HD), low-volume online hemodiafiltration (OL-HDF) and HighVolume OL-HDF.1Nowadays, HDF is becoming a preferred treatment modality for dialysis patients. The volume of substitution fluid delivered has been indicated as an independent mortality risk factor.
HighVolume OL-HDF was defined as substitution volume higher than the median substitution volume infused - median substitution fluid volume was 20.4 L. 442 patients were included in the study: incident hemodialysis and OL-HDF patients treated in 13 Fresenius Medical Care centres in Bosnia and Herzegovina, Serbia and Slovenia between January 1, 2007 and December 31, 2011.
Patients were assigned to OL-HDF and high-flux HD according to their treatment modality at baseline, and OL-HDF patients were retrospectively stratified to low-volume and high-volume groups if the median of substitution fluid volume delivered over the whole period, starting 3 months after baseline, was lower or higher than or equal to the median value for all patients together.
High-flux HD and OL-HDF treatments were performed on the Fresenius Medical Care 4008 and 5008 dialysis machines using polysulfone high-flux dialysers (Fresenius Medical Care, Bad Homburg, Germany) while HDF was conducted in post-dilution mode. Dialysis fluid and substitution fluid were ultrapure, defined as having < 0.1 colony-forming units per millilitre and < 0.03 endotoxin units per millilitre. Patients received treatment three times per week for a prescribed 240 minutes each to reach the target of single-pool Kt/V of 1.4. Primary study outcome was all-cause mortality.
As anemia plays a relevant role in the pathogenesis of cardiovascular disease,2 a secondary aim of this study was to investigate the effect of switching from high-flux HD to OL-HDF on erythropoietin consumption and resistance index. The hemoglobin target was 10–13 g/dL. Erythropoiesis stimulating agents (ESA) used were epoetin alpha, epoetin beta and darbepoetin alpha, while a factor of 1:200 was used to convert between darbepoetin units and epoetin units.
Main study outcome:
- Identification of the median substitution volume used for post-dilutional OL-HDF to be around 20L.
- HighVolume OL-HDF (median substitution volume > 20.4 L)—but not low-volume OL-HDF—was associated with improved survival compared to high-flux dialysis.
- Furthermore, OL-HDF was associated with a significantly lower ESA consumption and a significantly reduced ERI (erythropoietin resistance index).
This article supports the earlier published outcomes of the ESHOL study. This adds additional weight to the argument HDF can have significant clinical benefits when performed using high substitution volumes.
- Imamovic G, Hrvacevic R, Kapun S et al. Survival of incident patients on high-volume online hemodiafiltration compared to low-volume hemodiafiltration and high-flux hemodialysis. Int Urol Nephrol, 2013 Sept 21. [Epub ahead of print]
- Foley RN, Parfrey PS, Harnett JD, Kent GM, Murray DC, Barre PE (1996): The impact of anemia on cardiomyopathy, morbidity, and mortality in end-stage renal disease. Am J Kidney Dis 28:53–61