Mortality risk in patients on hemodiafiltration versus hemodialysis: a ‘real-world’ comparison from the DOPPS

Abstract

BackgroundWith its convective component, hemodiafiltration (HDF) provides better middle molecule clearance compared with hemodialysis (HD) and is postulated to improve survival. A previous analysis of Dialysis Outcomes and Practice Patterns Study (DOPPS) data in 1998–2001 found lower mortality rates for high replacement fluid volume HDF versus HD. Randomized controlled trials have not shown uniform survival advantage for HDF; in secondary (non-randomized) analyses, better outcomes were observed in patients receiving the highest convection volumes.MethodsIn a ‘real-world’ setting, we analyzed patients on dialysis >90 days from seven European countries in DOPPS Phases 4 and 5 (2009–15). Adjusted Cox regression was used to study HDF (versus HD) and mortality, overall and by replacement fluid volume.ResultsAmong 8567 eligible patients, 2012 (23%) were on HDF, ranging from 42% in Sweden to 12% in Germany. Median follow-up was 1.5 years during which 1988 patients died. The adjusted mortality hazard ratio (95% confidence interval) was 1.14 (1.00–1.29) for any HDF versus HD and 1.08 (0.92–1.28) for HDF >20 L replacement fluid volume versus HD. Similar results were found for cardiovascular and infection-related mortality. In an additional analysis aiming to avoid treatment-by-indication bias, we did not observe lower mortality rates in facilities using more HDF (versus HD).ConclusionsOur results do not support the notion that HDF provides superior patient survival. Further trials designed to test the effect of high-volume HDF (versus lower volume HDF versus HD) on clinical outcomes are needed to adequately inform clinical practices.

A review of the evidence for the use of haemodiafiltration

“…The Cochrane Review undertaken by Nistor et al (2015) supports this conclusion and could only find statistically significant evidence for patient improvement with respect to reduced mortality from CVD for patients receiving HDF. These findings have been replicated in the more recent large scale cohort study of DOPPS data completed by Locatelli et al (2017).…”

“…More recent analysis of DOPPS data by Locatelli et al (2017) has also concluded that HDF could not demonstrate improved patient survival over conventional HD therapy. This was a cohort study of patients aged 18 or over and receiving in-centre HD or HDF.…”

“…23% of the patients in the cohort were receiving HDF. Importantly, in their review of the literature Locatelli et al (2017) also acknowledge that little reliable data exists to confer any significant benefit in terms of mortality or morbidity to HDF over conventional HD.…”

“…Generally, these data, however, often lose significance once selection bias of patients chosen for HDF therapy are removed (Locatelli et al 2017). There is evidence from a number of individual studies that HDF can be beneficial for individual patients (Davenport et al 2010, Oates et al 2011, Maduell et al 2013, Dey et al 2015, Hill et al 2017 and for this reason many units have made the therapy available to increasing numbers of HD patients in recent years.…”

“…Some centres have adopted HDF as their standard treatment. Nephrologists according to Locatelli et al (2017) have cited dialysis-related amyloidosis, polyneuropathy, haemodynamic instability and longer life-expectancy as 'strong indicators' for prescribing HDF rather than HD.…”