Exploring vascular access survival in prevalent thrice-weekly in-centre nocturnal haemodialysis patients.

Background: This study explores vascular access complications in patients established on in-centre nocturnal haemodialysis (INHD) compared to conventional haemodialysis.

Methods: This was a retrospective cohort study; patients acted as their own control. Data were collected from three centres. Adults established on INHD (intervention) preceded by usual daytime haemodialysis (control) were eligible. Data were collected between 01/01/2009 and 12/31/2021. The data collection period was up to 12 months for both control and intervention periods. The primary outcome was a composite of outcomes related to vascular access complications: hospitalisation, intervention, change in vascular access modality, change in dialysis modality and death. The primary outcome was evaluated by time-to-event rate in days using Kaplan-Meier plots. Statistical significance was accepted at a P < 0.05.

Results: One hundred forty-five individuals were included: median age was 52.0 years (IQR 36.0-65.0), 71.0% (n = 103) were male, and 57.2% (n = 83) were White. The primary outcome occurred in 24.1% (n = 35) during the intervention and in 25.5% (n = 37) during the control period (P = 0.875). The 12-month vascular access survival probability was 73.4% (95%CI 65.8-81.0%) for the intervention and 70.6% (95%CI 62.4%-78.8%) for the control period. During the intervention period, arteriovenous grafts were associated with lower vascular access survival (P < 0.001). Regular vitamin K antagonist was associated with a lower 12-month vascular access survival for both the intervention (P = 0.044) and the control periods (P < 0.001).

Conclusion: There does not appear to be an increased risk to vascular access events for INHD compared to daytime haemodialysis. Vascular access type and regular anticoagulation were associated with a reduced vascular access survival probability.