Dr. Allon has had a long-standing research interest in vascular access for dialysis, culminating in over 100 peer-reviewed publications during the past 15 years, as well as several funded NIH grants on this topic. His short-term goal is to improve our understanding of the clinical outcomes of patients receiving arteriovenous fistulas (AVF) and grafts (AVG). His long-term goal is to develop novel approaches to improve these clinical outcomes. Approximately 80% of U.S. ESRD patients initiate hemodialysis (HD) with a central vein catheter (CVC). Once HD has been started the patient is referred to a surgeon for creation of a permanent vascular access, either an AVF or an AVG. The current consensus guidelines strongly recommend placing an AVF, rather than an AVG. However, several small observational studies have suggested that AVG may be a better choice than an AVF in elderly HD patients, due to the higher AVF failure rate and relatively short patient survival. Primary access failure leads to prolonged CVC-dependence, with its attendant complications, until another functioning vascular access is placed and suitable for HD. We hypothesize that in older HD patients who initiate HD with a CVC, placement of an AVG rather than an AVF will result in shorter CVC-dependence, fewer episodes of CRB, fewer hospitalizations and longer patient survival. We propose a retrospective cohort study focused on new ESRD patients age >65 years who initiate HD with a CVC and no secondary vascular access (AVF or AVG), and who receive a subsequent AVF or AVG within 6 months of initiating HD. We will compare the 2 patient cohorts (AVF vs. AVG) in terms of primary access failure rate, duration of CVC-dependence after access placement, frequency of CRB, frequency of infection-related hospitalization and all cause hospitalization, and overall patient survival. The results of this observational study will b used to (1) provide valuable information about clinical outcomes in elderly HD patients receiving an AVF vs. an AVG after initiation of HD, and (2) provide robust information necessary to design and perform a power analysis for a definitive randomized clinical trial of AVF vs AVG in this study population.

Public Health Relevance

There are about 400,000 hemodialysis patients in the U.S., and vascular access (fistula or graft) is imperative in order to deliver dialysis treatments. There is ongoing controversy about the relative merits of grafts and fistulas, particularly in elderly patients. The proposed study will compare clinical outcomes (hospitalizations, infections, and deaths) between elderly dialysis patients receiving grafts vs fistulas.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Exploratory/Developmental Grants (R21)
Project #
1R21DK104248-01A1
Application #
8967295
Study Section
Kidney, Nutrition, Obesity and Diabetes (KNOD)
Program Officer
Abbott, Kevin C
Project Start
2015-08-10
Project End
2017-06-30
Budget Start
2015-08-10
Budget End
2016-06-30
Support Year
1
Fiscal Year
2015
Total Cost
Indirect Cost
Name
University of Alabama Birmingham
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
063690705
City
Birmingham
State
AL
Country
United States
Zip Code
35294
Farrington, Crystal A; Robbin, Michelle L; Lee, Timmy et al. (2018) Postoperative Ultrasound, Unassisted Maturation, and Subsequent Primary Patency of Arteriovenous Fistulas. Clin J Am Soc Nephrol 13:1364-1372
Lee, Timmy; Qian, Joyce; Thamer, Mae et al. (2018) Gender Disparities in Vascular Access Surgical Outcomes in Elderly Hemodialysis Patients. Am J Nephrol 49:11-19
Lee, Timmy; Qian, Joyce; Thamer, Mae et al. (2018) Tradeoffs in Vascular Access Selection in Elderly Patients Initiating Hemodialysis With a Catheter. Am J Kidney Dis 72:509-518
Lee, Timmy; Thamer, Mae; Zhang, Qian et al. (2017) Vascular Access Type and Clinical Outcomes among Elderly Patients on Hemodialysis. Clin J Am Soc Nephrol 12:1823-1830
Lee, Timmy; Allon, Michael (2017) Reassessing Recommendations for Choice of Vascular Access. Clin J Am Soc Nephrol 12:865-867
Allon, Michael (2016) New Insights into Dialysis Vascular Access: Introduction. Clin J Am Soc Nephrol 11:1484-6
Lee, Timmy; Thamer, Mae; Zhang, Qian et al. (2016) Reduced Cardiovascular Mortality Associated with Early Vascular Access Placement in Elderly Patients with Chronic Kidney Disease. Am J Nephrol 43:334-40
Lee, Timmy; Thamer, Mae; Zhang, Yi et al. (2016) Association of Peritonitis with Hemodialysis Catheter Dependence after Modality Switch. Clin J Am Soc Nephrol 11:1999-2004
Lee, Timmy; Thamer, Mae; Zhang, Yi et al. (2015) Outcomes of Elderly Patients after Predialysis Vascular Access Creation. J Am Soc Nephrol 26:3133-40