#1804 Long-term outcomes of CKD patients with lupus nephritis: a nationwide cohort study

Abstract

Abstract Background and Aims Health trajectories of patients with lupus nephritis (LN) are poorly understood in the setting of moderate and advanced chronic kidney disease (CKD). Furthermore, data on comparison of outcomes of LN to other forms of CKD are scarce. Therefore, the aim of this study was to compare long-term outcomes between LN and CKD from other etiologies. Method Using data from the Swedish Renal Registry (2006-2021), we compared clinical outcomes between patients with moderate and advanced CKD related to LN (LN-CKD), and patients with CKD due to primary glomerular diseases (PGD-CKD, i.e. IgA nephropathy, focal segmental glomerulosclerosis, membranous nephropathy), and due to other common CKD etiologies with high cardiovascular risk (Other-CKD, mostly diabetes and nephrosclerosis). Cox proportional hazard models were used to estimate the adjusted hazard ratios of mortality, major cardiovascular events (MACE), heart failure (HF), kidney replacement therapy (KRT) and acute kidney injury (AKI). Models were adjusted for age, sex, comorbidities, clinical and biological data including kidney function, medications and healthcare utilization. Results At baseline, patients with LN-CKD (N = 317, 61 years, 76% women, median eGFR 30 mL/min per 1.73 m²) and PGD-CKD (N = 2296, 57 years, 30% women, eGFR 29 mL/min per 1.73 m²), were younger and had lower prevalence of cardiovascular disease than patients with Other-CKD (N = 34778, 75 years, 36% women, eGFR 25 mL/min per 1.73 m²). Over a median follow-up of 6.2 [3.3; 9.8] years, 19029 deaths (51%), 15768 (42%) MACE and 8390 (22%) KRT events occurred. The unadjusted 5-year absolute risks of death and MACE were high both in patients with LN-CKD (27% and 25%) and Other-CKD (50% and 44%), but lower in those with PGD-CKD (16% and 14%), whereas the 5-year absolute KRT risk was higher in patients with PGD-CKD (PGD-CKD: 37%, LN-CKD: 23%, Other-CKD: 23%). In multivariable analyses and as compared to PGD-CKD, patients with LN-CKD had a higher risk of death (adjusted HR: 1.63 [95% CI: 1.32-2.02]), MACE (1.65 [1.31-2.08]), HF (1.68 [1.31-2.14]) and AKI (1.45 [1.02-2.05]) and showed a lower risk of KRT (HR: 0.81 [0.64-1.02]), although the 95% CI slightly overlapped (Figure, panel A). In contrast, the risks of adverse events were similar between patients with LN-CKD and those with Other-CKD (Figure, panel B). Conclusion While LN-CKD had a lower risk of KRT than PGD-CKD, they exhibited a higher risk of death, MACE, KRT, HF and AKI, reaching the risk magnitude of patients with high cardiovascular burden (Other-CKD). Our findings may inform decisions for care planning in patients with advanced CKD and LN.