Effect of haemodiafiltration versus haemodialysis on vascular access patency when starting haemodialysis.

Background: Haemodiafiltration (HDF) therapy improves the prognosis by reducing inflammation and oxidative stress and improving endothelial function. These factors contribute to vascular access (VA) stenosis, one of the most common complications in patients on haemodialysis (HD) or HDF. This study aimed to assess the efficacy of HDF on VA patency.

Methods: This multicentre, prospective, observational study with post hoc analysis included 612 patients among 643 who underwent VA procedures and started dialysis between April 2012 and March 2021. A total of 516 patients were on HD since starting dialysis, while 96 switched to HDF after starting dialysis. One-to-one propensity score matching was performed to compare the 24-month patency rates of VA between groups by Kaplan-Meier and logrank tests, and a Cox proportional hazards regression analysis was used to identify factors affecting patency rates.

Results: There were 87 patients in each group. The 24-month primary patency rates were 74.2% for HDF and 47.7% for HD (P < .001). A multivariate Cox proportional hazards analysis showed that a history of cardiovascular disease {hazard ratio [HR] 2.29 [95% confidence interval (CI) 1.21-4.34], P = .01} and higher haemoglobin A1c values [HR 1.37 (95% CI 1.00-1.82), P = .04] were associated with poor 24-month primary patency. However, HDF [HR 0.30 (95% CI 0.16-0.56), P < .001] and use of statins [HR 0.50 (95% CI 0.27-0.94), P = .03] were associated with better patency. A stratified analysis showed that HRs for loss of VA patency were lower in patients with HDF than in those with HD in the subgroups of ≥65 years, male sex, radiocephalic arteriovenous fistula, a history of diabetes mellitus or cardiovascular disease, haemoglobin concentrations <10 g/dl and albumin concentrations <3.5 g/dl.

Conclusions: HDF potentially improves VA patency rates compared with HD, even in patients with cardiovascular disease or diabetes, commonly associated with poor patency.