Video
Animation – Long-Term Outcomes in IgA Nephropathy : Results From RaDaR
Understand the relationship between proteinuria and IgA nephropathy outcomes based on findings from the RaDaR registry for rare kidney diseases.
What is it about?
The UK National Registry of Rare Kidney Diseases (RaDaR) collects clinical data from patients with rare kidney diseases, such as IgA nephropathy.
Over 2,400 patients were included in the IgA nephropathy cohort of RaDaR.
Based on the 2021 Kidney Disease Improving Global Outcomes (KDIGO) 2021 Clinical Practice Guideline for the Management of Glomerular Diseases, healthcare professionals have previously grouped patients as “low risk” or “high risk”
- Low risk: Proteinuria <1 gram per day
- High risk: Proteinuria ≥1 gram per day
But more information on long-term outcome on low-risk IgA nephropathy was needed.
The following were measured:
- Proteinuria
- Kidney function
- Kidney survival
Outcomes in this large cohort of patients with IgA nephropathy were generally poor, including in patients traditionally considered “low risk” (<1 g/day)
- Few patients were expected to avoid kidney failure in their lifetime
- The data suggest that proteinuria had a strong predictive value for the progression of IgA nephropathy, including in low-risk patients
- Persistent proteinuria was significantly associated with more rapid loss of eGFR and worse kidney survival
In general, reducing proteinuria was associated with better outcomes in patients with IgA nephropathy.
Why is it important?
IgA nephropathy is the most common type of primary glomerulonephritis and leading cause of chronic kidney disease (CKD) and kidney failure.
To work toward the goal of preventing kidney failure in IgA nephropathy, the current approach to patient care needs to be re-evaluated to improve clinical outcomes.
Findings from the RaDaR study demonstrated a growing need to:
- Target a lower threshold of proteinuria than previously accepted and a lower eGFR loss
- Consider combination treatments to maximize effectiveness
- Implement a lower threshold for biopsy to allow for earlier diagnosis and treatment initiation
Using data in part from the RaDaR study, the 2025 KDIGO Clinical Practice Guideline for the Management of IgA Nephropathy and IgA Vasculitis (IgAV) have redefined risk of progressive loss of kidney function as ≥0.5 g/d.
MA-DS-24-0041 | October 2025
