Back‐up arteriovenous fistula in peritoneal dialysis patients: a retrospective cohort study of long‐term meaningful outcomes

BACKGROUND: Back-up arteriovenous fistula (bAVF) is used in peritoneal dialysis (PD) to avoid haemodialysis transfer via a central venous catheter (CVC). However, no previous study examined mortality or complications associated with bAVF creation. AIMS: Comparing mortality, haemodialysis transfer overall or with a CVC and vascular access complications (bAVF or CVC) between patients with a bVF and those with no bAVF. METHODS: A retrospective cohort study of adult PD patients within an Australian Local Health District (2017-2023). Cox regression models were used for hazard ratios (HR) and 95% confidence intervals (95% CI). RESULTS: Of 115 patents followed up (median of 1.9 years (interquartile range 0.9, 3.5)), 50 (44%) had a bAVF of which 31 (62%) matured. The bAVF group had 56 procedures (1.1/patient), including 32 assisted interventions (0.6/patient). There was no associated difference in mortality between bAVF and no bAVF group (HR 0.8, 95% CI 0.4-1.6, P = 0.6) or haemodialysis transfer (HR 1.0, 95% CI 0.5-2.0, P = 0.9). A bAVF was associated with a lower haemodialysis transfer risk with a CVC (HR 0.4, 95% CI 0.1-0.9, P = 0.04). Complications between the bAVF and no bAVF group were similar (28% vs 14%, P = 0.06). CONCLUSION: bAVF were associated with lower risk of haemodialysis transfer to haemodialysis with a CVC, compared to those with no bAVF. However, there was no difference in mortality, risk of transferring to haemodialysis or complications.