Meta-Analysis Evaluates Outcomes of Arteriovenous Fistula for Hemodialysis
October 18, 2017—In European Journal of Vascular and Endovascular Surgery (EJVES), Lauren C. Bylsma, MPH, et al published findings from a systematic review and meta-analysis of the efficacy and safety outcomes of arteriovenous fistulas for hemodialysis (2017;54:513–522). The aim of this study was to quantitatively summarize the outcomes of fistula patency, infection, maturation, and abandonment published in the scientific literature.
According to the investigators, arteriovenous fistulas are currently the recommended gold standard vascular access modality for hemodialysis because of their prolonged patency, improved durability, and low risk of infection for those that mature. However, notable disadvantages are observed in terms of protracted maturation time, associated high rates of catheter use, and substantial abandonment rates.
As summarized in EJVES, the investigators conducted literature searches in multiple databases to identify observational and interventional studies of mean fistula patency rates at 1 year, infection risk, maturation time, and abandonment. Digitization software was used to simulate individual patient level data from Kaplan-Meier survival plots.
More than 8,000 studies were reviewed, of which, 318 studies composed of 62,712 accesses, were included for analysis.
The investigators reported that the primary unassisted, primary assisted, and secondary patency rates for fistulas at 1 year were 64%, 73%, and 79%, respectively. However, not all fistulas reported as patent could be confirmed as being clinically useful for dialysis (ie, functional patency).
For fistulas that were reported as mature, mean time to maturation was 3.5 months; however, only 26% of created fistulas were reported as mature at 6 months and 21% of fistulas were abandoned without use. The overall risk of infection in fistula patients was 4.1%, and the overall rate of infection per 100 access days was 0.018.
The investigators concluded that reported fistula patency rates may overstate their potential clinical utility when time to maturation, maturation rate, abandonment, and infection are considered. Protracted maturation times, abandonment, and infection all have a significant impact on evaluating the clinical utility of fistula creation. A rigorous and consistent set of outcome definitions for hemodialysis access are necessary to clarify factors contributing to fistula success and the clinical consequence of fistula failure, advised the investigators in EJVES.