Effect of Hemodiafiltration or Hemodialysis on Mortality in Kidney Failure.

BACKGROUND: Several studies have suggested that patients with kidney failure may benefit from high-dose hemodiafiltration as compared with standard hemodialysis. However, given the limitations of the various published studies, additional data are needed. METHODS: We conducted a pragmatic, multinational, randomized, controlled trial involving patients with kidney failure who had received high-flux hemodialysis for at least 3 months. All the patients were deemed to be candidates for a convection volume of at least 23 liters per session (as required for high-dose hemodiafiltration) and were able to complete patient-reported outcome assessments. The patients were assigned to receive high-dose hemodiafiltration or continuation of conventional high-flux hemodialysis. The primary outcome was death from any cause. Key secondary outcomes were cause-specific death, a composite of fatal or nonfatal cardiovascular events, kidney transplantation, and recurrent all-cause or infection-related hospitalizations. RESULTS: A total of 1360 patients underwent randomization: 683 to receive high-dose hemodiafiltration and 677 to receive high-flux hemodialysis. The median follow-up was 30 months (interquartile range, 27 to 38). The mean convection volume during the trial in the hemodiafiltration group was 25.3 liters per session. Death from any cause occurred in 118 patients (17.3%) in the hemodiafiltration group and in 148 patients (21.9%) in the hemodialysis group (hazard ratio, 0.77; 95% confidence interval, 0.65 to 0.93). CONCLUSIONS: In patients with kidney failure resulting in kidney-replacement therapy, the use of high-dose hemodiafiltration resulted in a lower risk of death from any cause than conventional high-flux hemodialysis. (Funded by the European Commission Research and Innovation; CONVINCE Dutch Trial Register number, NTR7138.).

Physical performance tasks were linked to the PROMIS physical function metric in patients undergoing hemodialysis.

OBJECTIVES: To investigate whether a multi-item performance outcome measure, the physical performance test (PPT), can be calibrated to a common scale with patient-reported outcome measures, using the Patient-Reported Outcomes Measurement Information System (PROMIS) physical function (PF) metric. STUDY DESIGN AND SETTING: We analyzed baseline data (N = 1,113) from the CONVINCE study, an international trial in end-stage kidney disease patients comparing high-dose hemodiafiltration with high-flux hemodialysis. Assumptions of item response theory (IRT) modelling were investigated for the combined set of the nine-item PPT and a four-item PROMIS PF short form (PROMIS-PF4a). We applied unidimensional IRT linking for calibrating the PPT to the PROMIS PF metric. RESULTS: Although some evidence for multidimensionality was found, classical test statistics (Cronbach's Alpha = 0.93), Mokken (Loevinger's H = 0.50), and bifactor analysis (explained common variance = 0.65) indicated that PPT and PROMIS-PF4a items can be used to assess a common PF construct. On the group level, the agreement between PROMIS-PF4a and linked PPT scores was stable across several subsamples. On the individual level, scores differed considerably. CONCLUSION: We found preliminary evidence that the PPT can be linked to the PROMIS PF metric in hemodialysis patients, enabling group comparisons across patient-reported outcome and performance outcome measures. Alternative linking methods should be applied in future studies using a more comprehensive PROMIS PF item set.

CONVINCE in the context of existing evidence on haemodiafiltration.

Haemodiafiltration (HDF) provides a greater removal of larger solutes and protein-bound compounds than conventional high-flux haemodialysis (HD). There are indications that the patients receiving the highest convection volumes of HDF result in improved survival compared with HD. However, the comparative efficacy of HDF versus HD remains unproven. Here we provide a comparative account of the methodology and aims of 'the comparison of high-dose HDF with high-flux HD' (CONVINCE) study in the context of the totality of evidence and how this study will contribute to reaching a higher level of certainty regarding the comparative efficacy of HDF versus HD in people with end-stage kidney disease.

Clinical target achievement is associated with better quality of life among dialysis patients: results from a continuous quality improvement program in a Portuguese healthcare network.

BACKGROUND: Patients with kidney failure have multifaced clinical needs. Continuous quality improvement (CQI) programs initiated by large healthcare provider networks bear the promise of improving guideline adherence and improving patient-centered outcome, including health-related quality of life (HRQOL). We aimed at evaluating the association between key performance indicators (KPI) adopted for our CQI and HRQOL in a large network of dialysis providers. METHODS: We conducted a survey study in 39 centers belonging to the Portuguese Fresenius Medical Care (FME) network, in September 2017. For each participant, we retrospectively extracted clinical information during the 6-month period preceding survey administration. We used this information to calculate KPI as defined by the FME-CQI policy. Those KPI were selected in the FME-CQI policy as modifiable intermediate endpoints for which previous evidence suggested a causal relationship with patients' morbidity and mortality. HRQOL was assessed by the Kidney Disease Quality of Life Short Form 36 (KDQOL-36) questionnaire. RESULTS: Among 4691 eligible patients who were invited to participate in the survey, 2263 (48.2%) answered the self-administered survey. Based on KPI standards, patients had 1.5 (± 1.2) off-target clinical parameters on average. KDQOL-36 score were generally higher than those observed in European reference population. We found a significant linear association between KPI parameters and HRQOL. This pattern was robust to adjustment for satisfaction scores. CONCLUSIONS: Our data demonstrated a graded, monotonic, dose-response relationship between the number of off-target KPIs and HRQOL. Such relationship was not mediated by patients' satisfaction and may be attributed to amelioration of disease-specific symptoms and functional capacity.

Benefits and harms of high-dose haemodiafiltration versus high-flux haemodialysis: the comparison of high-dose haemodiafiltration with high-flux haemodialysis (CONVINCE) trial protocol.

INTRODUCTION: End-stage kidney disease (ESKD) is a major public health problem affecting more than 2 million people worldwide. It is one of the most severe chronic non-communicable diseases. Haemodialysis (HD) is the most common therapeutic option but is also associated with a risk of cardiovascular events, hospitalisation and suboptimal quality of life. Over the past decades, haemodiafiltration (HDF) has become available. Although high-dose HDF has shown some promising survival advantage compared to conventional HD, the evidence remains controversial. A Cochrane systematic review found, in low-quality trials, with various convective forms of dialysis, a reduction in cardiovascular, but not all-cause mortality and the effects on non-fatal cardiovascular events and hospitalisation were uncertain. In contrast, an individual patient data analysis suggested that high-dose HDF reduced both all-cause and cardiovascular mortality compared to HD. In view of these discrepant results, a definitive trial is required to determine whether high-dose HDF is preferable to high-flux HD. The comparison of high-dose HDF with high-flux HD (CONVINCE) study will assess the benefits and harms of high-dose HDF versus a conventional high-flux HD in adults with ESKD. METHODS AND ANALYSIS: This international, prospective, open label, randomised controlled trial aims to recruit 1800 ESKD adults treated with HD in nine European countries. Patients will be randomised 1:1 to high-dose HDF versus continuation of conventional high-flux HD. The primary outcome will be all-cause mortality at 3 years' follow-up. Secondary outcomes will include cause-specific mortality, cardiovascular events, all-cause and infection-related hospitalisations, patient-reported outcomes (eg, health-related quality of life) and cost-effectiveness. ETHICS AND DISSEMINATION: The CONVINCE study will address the question of benefits and harms of high-dose HDF compared to high-flux HD for kidney replacement therapy in patients with ESKD with a focus on survival, patient perspectives and cost-effectiveness. TRIAL REGISTRATION NUMBER: Netherlands National Trial Register (NTR 7138).