Supplementary Material for: Long-term outcomes in patients with renal systemic light chain amyloidosis

Introduction: Studies on the long-term outcomes of patients with predominant renal involvement and no significant extra-renal organ involvement in systemic light chain (AL) amyloidosis remain limited. Here we describe the outcomes of this population and examine the impact of the one year estimated glomerular filtration rate (eGFR) changes on mortality and renal survival. Methods：Patients with predominant renal involvement in AL amyloidosis who were diagnosed at National Clinical Research Center for Kidney Diseases of Jinling Hospital between 2010 and 2023 were included in this study. Medical records and follow-up data were collected. The primary endpoints, encompassing overall survival (OS) and renal survival, were analyzed using Kaplan-Meier and Cox regression. Results：A total of 351 patients (median age 56, range 31-83; 53.3% male) were enrolled, with 86.9% having an eGFR > 60 mL/min/1.73 m2 and median 24-hour proteinuria of 4.27 g/d. After a median follow-up of 60 months (range, 3-171 months), 65 patients (18.5%) were died and 60 (17.1%) had progressed to end-stage renal disease. The median OS was not reached, and the median renal survival was 157 months. The five-year OS and renal survival were 83.7% and 86.5%, respectively. Patients achieving at least a hematological and renal very good partial response exhibit significantly better outcomes. Within the first year, an eGFR decline of ≥5 mL/min/1.73m² (particularly ≥20 mL/min/1.73m2) was associated with increased dialysis risk, while a decline of ≥20 mL/min/1.73m2 was independently linked to elevated mortality risk. Conclusion：AL amyloidosis patients with predominant renal involvement have a relatively good prognosis and early eGFR decline has the potential value in prognostic assessment of renal AL amyloidosis.