Vascular access at Kidney Week: catheters needed the fewest procedures in the very old, and a bioengineered vessel shortened catheter time for women

🎧 Listen: Weekly · Oct 26, from 07:43.

The very old: OASIS (conference abstract, randomized trial)

Dutch investigators randomized adults aged 70 or older with a predicted life expectancy under two years, who were expected to start hemodialysis within six months or had started within six months with a catheter and were suitable for any access on vessel mapping, to a fistula, a graft or a catheter strategy. The trial enrolled 165 people (52 fistula, 57 graft, 56 catheter), with a mean age of 78, followed for a median of two years.

• According to the conference abstract, access-related procedures per patient-year were 0.76 with a catheter, 1.12 with a fistula and 1.53 with a graft. The catheter rate was significantly lower than the fistula rate (rate ratio 0.64; 97.5% CI, 0.42 to 0.98); the graft rate was not significantly different from the fistula rate, so that gap could be chance.
• Deaths and access-related infections did not differ significantly between groups. The trial was small and not designed to compare deaths or infections, so a difference can't be ruled out. The catheter-related bloodstream infection rate was 0.37 per 1,000 catheter days.
• The allocated access was changed most often in the graft group (24, against 9 with a fistula and 4 with a catheter), and grafts had the most access-related serious adverse events (0.27 per year, against 0.08 with a fistula and 0.11 with a catheter).

For balance: a large registry study (published, observational)

Dr. Nicholas Roetker and colleagues used US registry data on 536,836 adults aged 18 to 85 who started hemodialysis with a catheter from 2013 to 2022 and were living in the community and functionally independent. Using causal-inference methods, the adjusted 18-month risk of death remained higher with a catheter than with arteriovenous access, but the gap narrowed over the decade: from 5.9 to 4.2 deaths per 100 patients. The authors note that residual confounding is possible.

Women: a bioengineered vessel versus a fistula (conference abstract, phase 3 interim)

Women's fistulas mature less often, and women spend longer on catheters than men. This open-label phase 3 trial randomized women on hemodialysis through a catheter, who were eligible for a fistula, to an acellular tissue-engineered vessel or a fistula, with catheter-free days over 12 months as the primary outcome. In a prespecified interim analysis with 40 women per group, the conference abstract reports:

• Catheter-free days: 220 with the vessel vs 129 with a fistula (difference 91; 95% CI, 40 to 142).
• Time to use: 1.7 months vs 5.3 months.
• The trade-off: more thrombosis (20 vs 8 events) and stenosis (43 vs 36 events) with the vessel than with the fistula, although the stenosis rate adjusted for time in use was lower with the vessel.

The vessel (Symvess) is FDA approved for repairing arterial injury in the limbs after trauma. It is not approved for dialysis access; the company plans to apply for that indication.

Why it matters

Our take: in an 80-year-old with limited time, a catheter can be a plan, not a failure; ask how many procedures she'll face. And when you plan a fistula for a woman, ask how long she'll dialyze through a catheter while it matures, and talk that number through with her.

Caveats

Both trials are conference abstracts, so the full data haven't been peer reviewed. OASIS is small, and the vessel trial is an open-label interim analysis. The registry study is observational and limited to community-dwelling, functionally independent adults, so it says little about the frail, very old population in OASIS.

Funding and ties: OASIS had non-US government funding. The vessel trial was supported by Humacyte, and three authors are affiliated with Humacyte. The registry study was funded by the NIDDK.

The source: Heggen B, et al., for the OASIS Study Group. Arteriovenous Fistulas, Grafts, or Central Venous Catheters as Vascular Access for Older Adults Starting Hemodialysis: A Randomized Controlled Trial. ASN Kidney Week 2026, abstract TH-OR112 (conference abstract), October 22, 2026 Read the original

Also discussed:

• Hussain MA, et al. Acellular Tissue Engineered Vessel vs. Arteriovenous Fistula for Hemodialysis Access in Female Patients with ESKD: A Phase 3 CLN-PRO-V012 Interim Analysis. ASN Kidney Week 2026, abstract TH-OR113 (conference abstract) Link
• Roetker NS, Wetmore JB, Liu J, Gilbertson DT, Johansen KL. Trends in Mortality of Patients with Central Venous Catheters versus Arteriovenous Accesses for Hemodialysis. J Am Soc Nephrol. Published online October 22, 2026. doi:10.1681/ASN.0000001293 Link

🎧 Listen: Weekly · Oct 26, from 07:43.

Physician-led, AI-assisted. Dr. Wael Hussein chooses every item NephSpace covers and reviews and edits every story before it is published. The first draft was written in our own words with AI (Claude, by Anthropic) from the two conference abstracts and the full text of the registry paper and checked against our reading notes; Dr. Hussein then reviewed and edited it. For education and information only, not medical advice. Please talk to your own physician or care team about your health. Clinicians: read the original before changing practice. See our disclaimer and disclosures. Spotted an error? Tell us.