Abstract: TH-PO812
Plasma Galactose-Deficient IgA1/C3 Ratio Is Strongly Associated with Disease Progression in IgA Nephropathy
Session Information
- Glomerular Diseases: Immunology and Inflammation - I
October 25, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1202 Glomerular Diseases: Immunology and Inflammation
Authors
- Chen, Pei, Peking University First Hospital, Beijing, China
- Yu, Gui-zhen, Peking University First Hospital, Beijing, China
- Zhang, Xue, Peking University First Hospital, Beijing, China
- Shi, Sufang, Peking University First Hospital, Beijing, China
- Lv, Jicheng, Peking University First Hospital, Beijing, China
- Zhang, Hong, Peking University First Hospital, Beijing, China
Background
Galactose-deficient IgA1 (Gd-IgA1) and C3 mesangial codeposition is a hallmark of IgA nephropathy (IgAN). In this large cohort study, we aim to evaluate Gd-IgA1/C3 ratio in the progression of IgAN.
Methods
In this study, we included 1157 IgAN patients with a median follow-up period of 42 months. Plasma Gd-IgA1 was measured at the time of diagnosis using a lectin-based ELISA. The composite kidney failure event was defined by 50% decline in eGFR or ESRD and renal survival was modeled using the Cox proportional hazards method and restricted cubic splines.
Results
Although high plasma Gd-IgA1 levels were associated with the risk of kidney progression events, the association was not in a linear relationship. While the correlation between plasma Gd-IgA1/C3 ratio and risk of kidney failure was a linear relationship. After adjusted for traditional risk factors, higher levels of Gd-IgA1/C3 ratio was independently associated with a greater risk of deterioration in renal function with a HR of 2.15 (95% CI=1.21–3.81, P=0.008) per ln(Gd-IgA1/C3). In reference to the first quartile, the risk of kidney progression event increased such that the HR for the second quartile was 1.84 (95% CI=1.05–3.24, P=0.034), 1.79 (95% CI=1.02–3.12, P=0.041) for the third, and 2.08 (95% CI=1.22–3.54, P=0.007) for the fourth quartile of the Gd-IgA1/C3 ratio.
Conclusion
Plasma Gd-IgA1/C3 ratio was an independent risk factor for kidney progression events.
Cox regression model associations of baseline plasma Gd-IgA1/C3 levels with incidence of composite end point.
HR (95% CI) and P value | ||||
Unadjusted | Model 1 | Model 2 | Model 3 | |
Per ln(Gd-IgA1/C3) | 3.00 (1.73-5.21) | 3.02 (1.74-5.24) | 2.68(1.59-4.53) | 2.15(1.21-3.81) |
P value | 8.9×10-5 | 8.1×10-5 | 2.2×10-4 | 0.008 |
Gd-IgA1/C3 quartiles | ||||
1 | Reference | Reference | Reference | Reference |
2 | 1.68(0.99-2.85) | 1.61(0.94-2.76) | 1.63(0.95-2.80) | 1.84 (1.05-3.24) |
P value | 0.055 | 0.082 | 0.076 | 0.034 |
3 | 1.97(1.17-3.31) | 1.90(1.13-3.22) | 2.10(1.24-3.55) | 1.79 (1.02-3.12) |
P value | 0.010 | 0.016 | 0.006 | 0.041 |
4 | 2.49(1.51-4.12) | 2.47(1.49-4.07) | 2.29(1.39-3.80) | 2.08 (1.22-3.54) |
P value | 3.5×10-4 | 4.3×10-4 | 0.001 | 0.007 |
Model 1 was adjusted for sex and age. Model 2 was adjusted for covariates in model 1 plus eGFR, proteinuria, and mean arterial blood pressure. Model 3 was adjusted for covariates in model 2 plus Oxford MESTC scores and steroids or other immunosuppressive agents .