Survival rate on kidney dialysis similar for those with, without AAV
Higher risk of death associated with older age, low hemoglobin levels
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ANCA-associated vasculitis (AAV) patients with kidney failure requiring long-term dialysis have survival rates comparable to those of people with kidney failure due to other causes, according to a registry-based study in China.
Among the 54 AAV patients identified in the dialysis registry, death was mainly due to infections, and none was associated with AAV relapse. Older age, low levels of hemoglobin — the protein that carries oxygen in red blood cells — and using a central line to access a vein close to the heart for dialysis were associated with a higher risk of death in AAV patients.
“Although limited by sample size, the observed patterns highlight the importance of optimizing anemia [low hemoglobin] management, minimizing catheter use, and strengthening infection prevention strategies to improve outcomes for AAV patients receiving long-term dialysis,” the researchers wrote.
The study, “Long-term survival and mortality characteristics of patients with ANCA-associated vasculitis on maintenance hemodialysis: a propensity score-matched study from the Wuhan registry (2017–2025),” was published in BMC Nephrology.
Analysis included 54 people with AAV-associated kidney failure
AAV is a group of diseases characterized by inflammation and damage to small blood vessels, typically caused by self-reactive antibodies called ANCAs. AAV symptoms vary according to the organs involved, but kidney damage is common.
Without treatment, kidney damage may progress to kidney failure. In this case, patients may require dialysis, a procedure to filter waste and excess fluid from the blood when the kidneys can no longer perform this role, or a kidney transplant.
“Previous studies from Western [patient groups] have suggested that the survival of dialysis-dependent AAV patients is comparable to that of patients with other causes of [kidney failure], once the acute phase of the disease has passed,” the researchers wrote. “However, data from Asian populations, particularly from China, remain scarce.”
With this in mind, a team of researchers retrospectively analyzed 2017-2025 data from the Wuhan Dialysis Registry, which includes people on maintenance hemodialysis at one of 23 centers across the Wuhan province in China.
Hemodialysis is a type of dialysis that uses an external machine to pump blood through a filter that removes waste and fluids before returning the clean blood to the body.
A total of 9,430 patients were included in the study, of whom 54 (0.6%) had AAV as the primary cause of kidney failure. Eligible AAV patients were adults with at least three months of follow-up data.
AAV patients were matched with 162 people with kidney failure due to other causes in terms of age, sex, time on maintenance dialysis, dialysis modality, blood vessel access, and hospital level.
After 1 year, both groups had survival rates over 90%
The most common causes of kidney failure in the non-AAV group were diabetic nephropathy (30.2%), a kidney condition linked to diabetes, and primary glomerulonephritis (27.8%), which is marked by inflammation of the kidney’s filtering units.
Median follow-up duration was 31.5 months, or a little over 2.5 years, in the AAV group and 25.5 months — just over two years — in the non-AAV group. During the follow-up period, 54 people died, 12 with AAV and 42 without AAV. That’s about 22% and 26% of each group, respectively.
Overall survival was comparable between the groups. One year after initiating dialysis, the survival rate was 91.8% in AAV patients and 94.5% in the non-AAV group. Survival progressively decreased over time, reaching about 68% in both groups after five years.
In the AAV group, the mortality rate was higher among those who initiated hemodialysis during the 2020-2022 period, coinciding with the COVID-19 pandemic, than for those initiating the treatment in other years (31.8% vs. 15.6%).
This “likely reflects a complex mixture of factors, including infection risk, disruptions to dialysis delivery, constrained access to healthcare resources, and challenges in managing immunosuppression during periods of system stress,” the researchers wrote.
These findings suggest that conventional dialysis-related risk factors, rather than [AAV-specific] activity, play a dominant role in determining outcomes once AAV patients reach long-term dialysis.
AAV patients who died had initiated hemodialysis at a median age of 74 and received the treatment for 21 months, or nearly two years. In contrast, those who survived were younger at treatment initiation (median age of 66.5) and were on hemodialysis for more than three years.
Statistical analyses accounting for a single factor at a time showed that the risk of death increased by 9% per year of age at which hemodialysis was initiated and decreased by 4% for each 1 g/L increase in hemoglobin levels at the start of hemodialysis.
Also, hemodialysis using a central catheter, a flexible tube inserted into a large vein and threaded into a vein near the heart, was significantly associated with a four times higher risk of death compared with dialysis using an arteriovenous fistula (AVF). AVF is a surgically created connection between an artery and a vein, typically in the forearm, to provide access for hemodialysis.
The main cause of death among AAV patients was infections (66.7%), including COVID-19 (25%), followed by cardiovascular events (16.7%). No patient died due to problems associated with AAV relapse or worsening symptoms.
“These findings suggest that conventional dialysis-related risk factors, rather than [AAV-specific] activity, play a dominant role in determining outcomes once AAV patients reach long-term dialysis,” the researchers concluded.
