Early Failure of Dialysis Access among the Elderly in the Era of Fistula First.

Abstract

Recent evidence indicates that fistula maturation and patency may be compromised in the elderly dialysis population compared with younger patients. The objective of this study was to characterize the short-term outcomes of arteriovenous fistulas and arteriovenous grafts for hemodialysis access in the Medicare population. This was a retrospective cohort study performed using Medicare Part A and B claims data from 2006 through 2011. The study population included 16,464 dialysis-dependent patients age ≥66 years undergoing arteriovenous fistula and arteriovenous graft creation. The primary outcome measure was incidence of repeat fistula/graft creation and tunneled catheter placements in the 12 months after arteriovenous fistula and graft creation. In the 12 months postindex fistula/graft, the mortality in the fistula group was 28.2% versus 29.9% in the graft group (P=0.03). A repeat fistula/graft creation was required in 26.9% of patients in the fistula group and 16.7% in the graft group (P<0.001). There was no significant difference in the proportion of patients who required a tunneled hemodialysis catheter in the 12 months after an index fistula creation (fistula 28.4% versus graft 27.3%, P=0.19). In the index fistula group, 44.4% of patients required a repeat fistula/graft creation and/or a tunneled catheter, compared with 33.7% in the graft group (P<0.001). At 365 days after the index fistula/graft, the repeat fistula/graft/catheter-free survival was 39.7% in the fistula group versus 46.0% in the graft group (P<0.001). Index fistula was associated with a higher risk of loss of repeat fistula/graft/catheter-free survival with an odds ratio of 1.19 (95% confidence interval, 1.13 to 1.24). Fistulas were associated with a somewhat lower mortality than grafts in the first 12 months after creation. However, the incidence of repeat fistula/graft creation and tunneled catheter placement is substantially higher in the first 12 months after fistula creation compared with grafts. One-year repeat fistula/graft/catheter-free survival is lower after fistula creation than grafts.