Association between serum IgG concentrations and prognosis in IgA nephropathy patients
10.3760/cma.j.cn441217-20240617-00624
- VernacularTitle:血清IgG浓度与IgA肾病患者肾脏预后的相关性分析
- Author:
Fei TANG
1
;
Ricong XU
;
Haofei HU
;
Yuan CHENG
;
Rong CAO
;
Cai TAO
;
Xueqing YU
;
Wei CHEN
;
Qijun WAN
Author Information
1. 深圳市第二人民医院肾内科，深圳 518025
- Publication Type:Journal Article
- Keywords:
Glomerulonephritis, IgA;
Immunoglobulin G;
Prognosis;
Correlation analysis
- From:
Chinese Journal of Nephrology
2025;41(7):498-506
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the association between serum IgG concentration and renal prognosis in patients with IgA nephropathy (IgAN).Methods:It was a multi-center retrospective cohort study, patients with biopsy proven primary IgAN who were recorded in the Chinese IgA Nephropathy Information Registration System between April 1996 and September 2018 were included. Exclusion criteria were: (1) age <18 years; (2) <8 glomeruli in biopsy specimens; (3) estimated glomerular filtration rate (eGFR) <15 ml·min -1·(1.73 m 2) -1 at biopsy; (4) missing baseline serum IgG values; (5) incomplete follow-up data; (6) follow-up duration <12 months. Enrolled patients were divided into 3 groups according to the baseline tertiles of serum IgG: ≤9.50 g/L (G1 group), 9.51-11.99 g/L (G2 group), and ≥12.00 g/L (G3 group). Clinical, and pathological parameters were compared across groups. The endpoint events were defined as doubled serum creatinine level from baseline, or end-stage renal disease (ESRD). Results:A total of 1 976 IgAN patients were included in this study, 631 were in G1 group, 664 in G2 group, and 681 in G3 group. The comparison of baseline clinical data showed that there were statistically significant differences among the three groups in terms of gender, age, microscopic hematuria, edema, body mass index, systolic blood pressure, diastolic blood pressure, hemoglobin, serum creatinine, eGFR, 24-hour urine protein quantity, blood uric acid, blood albumin, serum IgA, serum IgM, the proportion of using immunosuppressants, and the proportion of using glucocorticoids (all P<0.05). In terms of pathology, the higher the serum IgG concentration, the relatively less severe the overall renal pathological damage. The results of univariate Cox regression analysis showed that gender, systolic blood pressure, diastolic blood pressure, hemoglobin, serum creatinine, eGFR, 24-hour urine protein quantity, total protein, serum albumin, globulin, serum IgG, Oxford renal pathological classification, glomerular sclerosis ratio, and glomerular IgM deposition were all associated with the occurrence of renal endpoint events (all P<0.05). Based on clinical practice and previous studies, after adjusting for gender, age, systolic blood pressure, diastolic blood pressure, eGFR, 24-hour urine protein quantity, body mass index, Oxford renal pathological classification, glomerular sclerosis ratio, and the use of renin-angiotensin-aldosterone system inhibitors, glucocorticoids, and immunosuppressants, multivariate Cox regression analysis showed that as a continuous variable, the baseline serum IgG level ( HR=0.91, 95% CI 0.87-0.96) was independently associated with the risk of renal endpoint events in IgAN patients; as a categorical variable, with serum IgG ≤ 9.50 g/L as the reference, serum IgG 9.51-11.99 g/L and serum IgG ≥ 12.00 g/L were independent factors for the occurrence of renal endpoint events in IgAN patients ( HR=0.69, 95% CI 0.49-0.96, P=0.027; HR=0.50, 95% CI 0.34-0.74, P<0.001). During a median follow-up of 33(21, 53) months started from the date of renal biopsy and continued until December 31, 2019, the median follow-up duration was 33 (21, 53) months, and a total of 232 patients (11.74%) reached the composite endpoint. Kaplan-Meier survival analysis showed that the higher the serum IgG concentration in patients with IgAN, the higher their cumulative renal survival rate (Log-rank test, χ2=47.176, P<0.001). Conclusion:The higher level of serum IgG at diagnosis is associated with better clinicopathologic features and renal outcomes, and may portend better renal survival in IgAN patients.
