Arterial stiffness: hemodialysis versus hemodiafiltration.

Background and aims: Arterial stiffness seems to be influenced by the dialysis method, but studies are sparse and the results discordant. High substitution volume online hemodiafiltration appears to have beneficial cardiovascular effects in dialysis patients, but its effects on arterial stiffness are not investigated. We aimed to analyze arterial stiffness parameters in high substitution volume post-dilution online hemodiafiltration and compare results to high-flux hemodialysis.

Methods: We studied arterial stiffness parameters using the oscillometric method (Arteriograph IrDA, TensioMed, Budapest, Hungary) in 23 non-diabetic patients on high substitution volume online postdilution hemodiafiltration and 23 non-diabetic patients on high-flux hemodialysis. Dialysis vintage was at least 6 months in all subjects.

Results: Hemodiafiltration-treated patients showed a more favorable arterial stiffness profile. Pulse wave velocity was significantly higher in hemodialysis compared to hemodiafiltration patients (10.39±2.29 m/s vs 9.0±1.7 m/s, p=0.026). Augmentation indexes and the diastolic reflection area were also significantly elevated hemodialysis patients compared to hemodiafiltration patients.

Conclusions: High substitution volume online postdilution hemodiafiltration could have a beneficial effect on arterial stiffness and should be assessed in properly sized controlled trials.