Supplementary Material for: Predictors of Kidney Outcomes of Anti-Glomerular Basement Membrane Disease in a Large Chinese Cohort

Introduction: Anti-glomerular basement membrane (GBM) disease is a rare but the most aggressive form of glomerulonephritis. To dissect the prognostic factors, we retrospectively analyzed the clinical features of a large cohort and compared the clinical features and prognosis during decades. Methods: Data on clinical manifestation, treatment, and prognosis were collected. Cox models and receiver operating characteristic (ROC) curve were used to investigate the predictors for outcomes. The Kaplan-Meier curve and log-rank test were used to compare kidney and patient survival. Results: A total of 448 patients were enrolled. Patient survival and kidney survival at 1 year was 69.4% and 37.7%, respectively. During the past 3 decades, mortality at 3 months and 1 year significantly dropped from 37.5% and 57.1% in 1991–2000 to 2.8% and 6.9% in 2011–2020 (p < 0.001), respectively; kidney prognosis showed a tendency of improvement as well. Serum creatinine (Scr) on diagnosis (HR, 1.16; 95% CI, 1.05–1.29) and crescent percentage (HR, 1.73; 95% CI, 1.34–2.24) were independent predictors for end-stage kidney disease. ROC curve showed that the optimal cutoff point of Scr on diagnosis for prediction of dialysis dependency at 1 year was 536.4 μmol/L (sensitivity 88.3% and specificity 80.8%). Antineutrophil cytoplasmic antibodies (ANCAs) positivity (HR, 4.43; 95% CI, 1.72–11.38) was a predictor for mortality. Plasma exchange was associated with a better patient prognosis (HR, 0.40; 95% CI 0.16–0.95). Conclusion: Scr on diagnosis and percentage of crescents were predictors for kidney outcomes. Positive ANCA was a predictor for mortality. Overall patient prognosis of anti-GBM disease was improved during the past 3 decades.