Supplementary Material for: Treatment with Haemodiafiltration Stabilises Vascular Stiffness (Measured by Aortic Pulse Wave Velocity) Compared to Haemodialysis

Background/Aims: Cerebrovascular diseases such as stroke are increased in dialysis patients, and haemodiafiltration has been reported to reduce cerebrovascular mortality compared to haemodialysis. We wished to determine whether haemodiafiltration improves arterial stiffness. Methods: We audited aortic pulse wave velocity (PWV) measurements 6 months apart in 3 cohorts of patients: 69 treated with haemodialysis, 78 who converted from haemodialysis to haemodiafiltration and 142 treated with haemodiafiltration. Results: Cohorts were well matched for age (means ± SD: haemodialysis 64 ± 15 years vs. haemodialysis to haemodiafiltration 64 ± 17 years vs. haemodiafiltration 67 ± 16 years), sex (male 65 vs. 59 vs. 63%), diabetes (45 vs. 56.4 vs. 44%) and body mass index (26 ± 6 vs. 26 ± 5 vs. 26 ± 5), respectively. Systolic blood pressure did not differ over time (haemodialysis 143 ± 25 vs. 146 ± 27 mm Hg, haemodialysis to haemodiafiltration 153 ± 26 vs. 154 ± 25 mm Hg, haemodiafiltration 149 ± 31 vs. 148 ± 30 mm Hg) or between groups. Aortic PWV significantly increased in the haemodialysis group (9.5 ± 1.9 vs. 10.2 ± 2.2 m/s, p < 0.01) and haemodialysis to haemodiafiltration group (9.4 ± 1.9 vs. 10.1 ± 2.2 m/s, p < 0.01), but did not change with haemodiafiltration (9.9 ± 2.1 vs. 10.1 ± 2.2 m/s). Conclusions: Aortic PWV, a measure of vascular stiffness, stabilised with haemodiafiltration. Our preliminary findings require further investigation to determine how haemodiafiltration may potentially improve vascular stiffness.