Arteriovenous Graft Failure in the Veterans Health Administration: Outcome Disparities Associated with Race.

Background Vascular access for ongoing hemodialysis often fails, frequently requiring repeated procedures to maintain vascular patency. While research has shown racial discrepancies in multiple aspects of renal failure treatment, there is poor understanding of how these factors might relate to vascular access maintenance procedures after arteriovenous graft (AVG) placement. Purpose To evaluate racial disparities associated with premature vascular access failure after percutaneous access maintenance procedures following AVG placement using a retrospective national cohort from the Veterans Health Administration (VHA). Materials and Methods All hemodialysis vascular maintenance procedures performed at VHA hospitals between October 2016 and March 2020 were identified. To ensure the sample represented patients who consistently used the VHA, patients without AVG placement within 5 years of their first maintenance procedure were excluded. Access failure was defined as a repeat access maintenance procedure or as hemodialysis catheter placement occurring 1-30 days after the index procedure. Multivariable logistic regression analyses were performed to calculate prevalence ratios (PRs) measuring the association between hemodialysis maintenance failure and African American race compared with all other races. Models controlled for vascular access history, patient socioeconomic status, and procedure and facility characteristics. Results In total, 1950 access maintenance procedures in 995 patients (mean age, 69 years ± 9 [SD], 1870 men) with an AVG created in one of 61 VHA facilities were identified. Most procedures involved African American patients (1169 of 1950, 60%) and patients residing in the South (1002 of 1950, 51%). Premature access failure occurred in 215 of 1950 (11%) procedures. When compared with all other races, African American race was associated with premature access site failure (PR, 1.4; 95% CI: 1.07, 1.43; P = .02). Among the 1057 procedures in 30 facilities with interventional radiology resident training programs, there was no evidence of racial disparity in the outcome (PR, 1.1; P = .63). Conclusion African American race was associated with higher risk-adjusted rates of premature arteriovenous graft failure after dialysis maintenance. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Forman and Davis in this issue.

RUSC2 and WDR47 oppositely regulate kinesin-1-dependent distribution of ATG9A to the cell periphery.

Autophagy-related protein 9 (ATG9) is a transmembrane protein component of the autophagy machinery that cycles between the trans-Golgi network (TGN) in the perinuclear area and other compartments in the peripheral area of the cell. In mammalian cells, export of the ATG9A isoform from the TGN into ATG9A-containing vesicles is mediated by the adaptor protein 4 (AP-4) complex. However, the mechanisms responsible for the subsequent distribution of these vesicles to the cell periphery are unclear. Herein we show that the AP-4-accessory protein RUSC2 couples ATG9A-containing vesicles to the plus-end-directed microtubule motor kinesin-1 via an interaction between a disordered region of RUSC2 and the kinesin-1 light chain. This interaction is counteracted by the microtubule-associated protein WDR47. These findings uncover a mechanism for the peripheral distribution of ATG9A-containing vesicles involving the function of RUSC2 as a kinesin-1 adaptor and WDR47 as a negative regulator of this function.