High-dose hemodiafiltration demonstrates remarkable mortality benefits for kidney failure patients compared with hemodialysis: The CONVINCE trial

19 Jul 2023

Previous randomized, controlled trials have provided inconclusive results on whether the dialysis techniques, hemodiafiltration or hemodialysis, possessed superior survival benefits for patients with kidney failure.1 The CONVINCE trial took this issue a step further to compare high-dose hemodiafiltration with hemodialysis for their survival outcomes.1 Results of this study suggested that the implementation of high-dose hemodiafiltration provided more beneficial survival outcomes for patients with end-stage kidney disease.1  

Hemodiafiltration and hemodialysis are the conventional therapies for treating kidney failure, with hemodialysis being more commonly utilized.1 Nevertheless, a recent meta-analysis has illustrated the possibility that hemodiafiltration might positively impact the survival outcomes for patients with end-stage kidney disease, reducing the risk of overall and cardiovascular (CV) mortality by 14% and 23%, respectively.2 Results of this meta-analysis also suggested a potential correlation of patients who received high-dose hemodiafiltration having more favorable survival outcomes.2 As such, CONVINCE study was conducted to elucidate the survival benefits between high-dose hemodiafiltration and high-flux hemodialysis.

The CONVINCE trial was an international, prospective, open-label, multicenter, pragmatic, randomized, controlled trial that enrolled 1,360 adult patients who were diagnosed with stage V kidney failure, had previously received hemodialysis treatment for at least 3 months, and was eligible for high-dose hemodiafiltration (i.e., ≥23 liters of convection volume in post-dilution mode per session).1 The participants were randomized 1:1 to initiate either high-dose hemodiafiltration or continue the high-flux hemodialysis treatment.1 The primary endpoint of this study was the overall mortality of the patient groups.1 The key secondary endpoints consisted of cause-specific mortality, the composite outcome of fatal and non-fatal CV events, kidney transplantation, and recurrent hospitalization for any causes and for causes relating to infection.

With a median follow-up period of 30 months, the analysis results of the study highlighted the survival benefits of high-dose hemodiafiltration, as the study observed a 23% reduction in the overall mortality risk with the use of high-dose hemodiafiltration compared with high-flux hemodialysis (HR=0.77; 95% CI: 0.65-0.93; p=0.005).1 Subsequently, the survival outcomes differed in accordance with the patient’s preexisting medical history.1 Notably, more pronounced survival outcomes were observed among patients without CV diseases (HR=0.58; 95% CI: 0.42-0.79) and patients without diabetes mellitus (HR=0.65; 95% CI: 0.48-0.87) in both treatment groups.1 Additionally, the study also concluded a marked decline in the mortality risk in senior patients aged ≥65 years, with a hazard ratio of 0.68 in the high-dose hemodiafiltration cohort (95% CI: 0.53-0.89).

As to the secondary endpoints, the risk of death from CV events (HR=0.81; 95% CI: 0.49-1.33), the composite outcome of fatal and non-fatal CV events (HR=1.07; 95% CI: 0.86-1.33), the rates of recurrent non-fatal hospitalization (HR=1.11; 95% CI: 0.98-1.25), the rate of infection-related hospitalization including Coronavirus disease 2019 (COVID-19) (HR=1.06; 95% CI: 0.86-1.30) and excluding COVID-19 (HR=0.97; 95% CI: 0.74-1.26) were similar, while no significant difference was present between the 2 cohorts.1 Nevertheless, high-dose hemodiafiltration treatment was associated with a decreased risk of infection-related death by 31% (HR= 0.69; 95% CI: 0.49-0.96).1 

To conclude, high-dose hemodiafiltration has been shown to provide more desirable survival outcomes compared with the conventional high-flux hemodialysis among patients with kidney failure in the CONVINCE trial.1 Thus, the results of this trial encourage further studies to investigate whether the survival benefits of high-dose hemodiafiltration are broadly applicable to other patient populations and subgroups.

  1. Blankestijin PJ, et al. Effect of Hemodiafiltration or Hemodialysis on Mortality in Kidney Failure. N Engl J Med. 2023. 

  1. Peters SA, et al. Haemodiafiltration and mortality in end-stage kidney disease patients: a pooled individual participant data analysis from four randomized controlled trials. Nephrol Dial Transplant. 2016; 31: 978-984.