Anticoagulation in Dialysis Vascular Access

Background: Hemodialysis (HD) patients with dialysis access, arteriovenous fistula (AVF) or arteriovenous graft (AVG), are often placed on anticoagulation to for prevention of future thrombosis. We conducted a retrospective study comparing AVF/AVG thrombosis rates in HD patients with and without anticoagulation within an integrated healthcare network. Methods: Kaiser Permanente Northern California is an integrated health care system taking care of 4.6 million members. We identified patients on dialysis between Jan 1, 2013, to Dec 31, 2021, who were placed on anticoagulation vs. not. Dialysis initiation date is used as index date. Anticoagulation was started after index date. We compared the AVF and AVG thrombosis rate within one year after the dialysis initiation date. Results: We identified 9079 patients on hemodialysis in the study period, among them, 7242 did not use anticoagulation and 1837 did. The baseline demographics and comorbidities Indicating an older anticoagulation cohort, has higher Charlson comorbidity Index, HTN, PVD and less use of ASA (table). After one year, the rate of both fistula thrombosis is similar. The graft thrombosis is higher in the anticoagulant patients than non-anticoagulant patients (figure). Conclusion: In this retrospective study, hemodialysis patients on anticoagulation did not have lower rate of AVF/AVG thrombosis. Baseline patient characteristics might explain this difference. Randomized prospective studies are needed to compare the effect of anti-coagulation in dialysis vascular access patency.