DOPPS research details U.S., international practice patterns on access placement

On many levels, the United States offers the best health care in the world – except when it comes to access placement for dialysis patients.

Data from the Dialysis Outcomes and Practice Patterns Study on access use and cannulation techniques, presented during a May 7 webinar and in a just-released paper in a leading nephrology journal, confirmed the U.S. renal community’s “Achilles’ heel” when it comes to optimal vascular access.

The DOPPS data, based on the research groups’ Practice Monitor – a sampling of 200 clinics and 14,000 patients in the U.S.—and ongoing international studies, details where the U.S. ranks with other countries in placing the arteriovenous fistula, considered the gold standard for dialysis patients.

Access options for dialysis patients: A surgeon’s view

The arteriovenous fistula may be the gold standard for dialysis access, but it may not always be the best option for some patients – particularly those who have already had multiple failed accesses.

Some conclusions from the presentation on May 7, with U.S. data gathered by DOPPS through December 2014, and the article in the American Journal of Kidney Diseases, include:

At 84%, Japan does the best job of placing fistulas early on in dialysis treatment (patients placed on dialysis ≤ 60 days at the start of DOPPS enrollment). It is the highest among 14 countries or geographic regions under review by the DOPPS researchers. Turkey was next at 66%, and Italy at 58% of patients who start dialysis with a fistula. Other countries with a percentage ranging from 56% to 50% were Germany, United Kingdom, Russia, and Spain. The United States was 11^th with 28%, equal to Canada.

Among prevalent patients, however, Russia had the highest number of patients with a fistula (92%). Japan was next, followed by China and Turkey. Seven countries had fistulas in place for at least 80% of prevalent patients. The U.S. ranked a respectable eighth, tied with Italy, showing 66% of patients with fistulas and 15% with catheters in use.

Placing fistulas early in patients in the U.S. is elusive, even among those who see a nephrologist prior to dialysis. Incentives may be needed to bring placement of AV fistulas in line with placement among prevalent patients. “AVF use at dialysis therapy initiation remains low, suggesting that reforms affecting predialysis care may be necessary to incentivize improvements in fistula rates at dialysis therapy initiation as achieved for prevalent hemodialysis patients,” wrote Ronald Pisoni, PhD, and DOPPS colleagues in the AJKD paper, “Trends in U.S. vascular access use, patient preferences, and related practices: An update from the US DOPPS Practice Monitor with international comparisons.” Among incident U.S. hemodialysis patients, 60% are starting with a catheter even after having at least four months of predialysis nephrology care, the DOPPS data shows.

To review this issue, data was collected on patients who entered the study within 60 days of their first hemodialysis treatment for ESRD. DOPPS data showed that, among these patients, they exhibited the lowest uses of an AVF at study entry, with 28% using an AV fistula; 5%, an AV graft; and 67% a central venous catheter. In contrast, AVF use among incident patients at study entry was 50% to 60% in most European countries and, as noted, 84% in Japan.

The low AVF use in new hemodialysis patients was seen in the United States although nearly 70% of these patients had seen a nephrologist four or more months prior to ESRD.

Who gets an AV fistula?

The DOPPS researchers also looked at ethnic correlations with access type, and the connection between males and females and access type. As noted in the AJKD article, they found that:

AV graft use was twice as high in black patients (26%) in the DOPPS U.S. sampling than in others in the U.S.

Only 58% of black patients had arteriovenous fistulas; that compared with 74% in Hispanic patients and 70% in white patients.

Education about the value of a better access needs to improve, the researcher said, with 16% to 20% of patients feeling uninformed regarding benefits/risks of different vascular access types.

Central venous catheter use was 1.4- to 1.5-fold higher in female versus male hemodialysis patients.

Catheter use in U.S. prevalent hemodialysis patients was lower in black versus non-black prevalent hemodialysis patients. Lower AVF use in black patients may be explained in part by significantly smaller median basilic and cephalic vein diameters in African American males undergoing AV access surgery, as detailed in recent reports, the researchers wrote.

U.S. hemodialysis facilities report "typical" times to first arteriovenous fistula cannulation that are generally longer than most other countries in the DOPPS.

More information on the DOPPS’ May 7 presentation can be found at www.dopps.org/DPM/EmergingTrends.aspx, including downloadable Powerpoint slides on trends in vascular access placement.

A closer look at race and access placement

Black and Hispanic patients will start hemodialysis with an arteriovenous fistula less frequently than white patients, according to a report published online by JAMA Surgery.

Mahmoud B. Malas, MD, MHS, of the Johns Hopkins Medical Institutions, Baltimore, and coauthors examined national trends in initial hemodialysis access with respect to race/ethnicity further divided by co-existing illnesses, nephrology care, and medical insurance status. Their study was a retrospective analysis of 396,075 patients with end-stage renal disease in the U.S. Renal Data System who started dialysis from 2006 through 2010. The main outcomes of the study were utilization rates of arteriovenous fistula, arteriovenous graft, and intravascular hemodialysis catheter. Most of the patients (55.4%) in the study were white, followed by 30.3% black patients and 14.3% Hispanic patients.

The authors found that more white patients initiated hemodialysis with an AVF than black or Hispanic patients (18.3% vs. 15.5% and 14.6%, respectively), although black and Hispanic patients tended to be younger and had less coronary artery disease, chronic obstructive pulmonary disease, and cancer than white patients with an AVF. Regardless of medical insurance status, both black and Hispanic patients started hemodialysis with an AVF less frequently than white patients. AVF utilization at initial hemodialysis also was lower among black patients and Hispanic patients compared with white patients among patients who had nephrology care for longer than one year.

The authors note it is possible black and Hispanic patients with chronic kidney disease may be progressing too quickly to ESRD to make AVFs a viable initial hemodialysis access option because AVFs generally take six to 12 weeks to mature and grow stronger.

"The racial/ethnic disparities in incident AVF access that we describe deserve elucidation. The high rates of catheter use despite national programs to reverse this trend is unacceptable. ...The sociocultural underpinnings of these disparities deserve investigation and redress to maximize the benefits of initiating hemodialysis via fistula in patients with ESRD [end-stage renal disease] irrespective of race/ethnicity," the study concludes.

"Their analysis of the U.S. Renal Data System contributes useful insight into racial/ethnic differences in arteriovenous fistula (AVF) utilization, accounting for patient comorbidities, insurance status and health care provider specialty, but the overall rates of AVF use (or more appropriately the lack of AVF use) at first hemodialysis are perhaps the more important and concerning finding," wrote Laura A. Peterson, MD, MS, and Matthew A. Corriere, MD, MS, of the Wake Forest School of Medicine in a related commentary. “Rates of AVF use at hemodialysis initiation were 18.3%, 15.5% and 14.6% among white, black and Hispanic patients, respectively. These results are especially sobering compared with the 2006 goals from the National Kidney Foundation, including prevalent functional AVF in more than 65 percent of patients and cuffed catheters in less than 10%.

“... Given the mismatch between goals and current outcomes, the more appropriate quality improvement focus may be lowering the dismal overall catheter rates instead of a less than 5 percent difference in AVF rates between races/ethnicities," Peterson and Corriere wrote.

NKF takes steps to begin revision to KDOQI guidelines for access

The National Kidney Foundation has put together a new team to begin revisions to the Kidney Disease Outcomes Quality Initiative vascular access guidelines. Vascular access was one of the three original Dialysis Outcomes Quality Initiative guidelines released by the NKF in 1997 and was updated as part of the Kidney Disease Outcomes Quality Initiative in 2006. “We are currently refining a scope of work and considering potential workgroup members. At this point it is looking like a lot of new evidence has accumulated, and that the update will include some substantial changes. There will be strong emphasis on access failure prevention and early detection, as well as on treatment. Within treatment, there will most likely be separate sections devoted to fistula/graft complications, and catheter-related infection,” an NKF spokesperson told NN&I. Literature review for the revisions are expected to begin in late spring/early summer 2015.

Vascular Access Workgroup (Chairs)

Charmaine Lok, MD, FRCPC, MSc, University of Toronto, Board of Directors, Vascular Access Society of the Americas

Alex Yevzlin, MD, University of Wisconsin, president, American Society of Diagnostic and Interventional Nephrology

Surendra Shenoy, PhD, FACS, Washington University, president, Vascular Access Society of the Americas

Access tool kit available from the NCC

The End Stage Renal Disease National Coordinating Center (ESRD NCC) has created some new vascular access materials and enhancements to the Lifeline for a Lifetime toolkit for patients and professionals. These tools were developed by the Fistula First Catheter Last (FFCL) Workgroup Coalition as part of its ongoing efforts to increase the use of AV fistulas and decrease the use of tunneled dialysis catheters. The newest tools include resources for the One Minute Catheter Check and a Spanish language version of the Access Planning Manual. The complete toolkit for patients and providers can now be found in one central location and includes the following educational resources encouraging the one-minute catheter check, vascular access planning, and vascular access monitoring:

Videos that can now be downloaded and saved for continued use

Downloadable PDFs and interactive files for patients and professionals

Patient resources available in both English and Spanish

Resource Download Center for convenient access to and downloading of all educational materials

These materials are available at http://esrdncc.org/lifeline-for-a-lifetime or the ESRD NCC’s online Resource Download Center.