Clinical, Histologic, and Serological Predictors of Renal Function Loss in Lupus Nephritis

OBJECTIVE: Kidney survival is the ultimate goal in lupus nephritis (LN) management, but long-term predictors remain inadequately studied, requiring long-term follow-up. This study aimed to identify baseline and early longitudinal predictors of kidney survival in the Accelerating Medicines Partnership LN longitudinal cohort. METHODS: We performed time-to-event analyses of clinical, centrally scored histologic, and serological predictors of kidney function loss (sustained ≥40% estimated glomerular filtration rate [eGFR] decline or progression to end-stage kidney disease) in 172 LN patients with a median follow-up of 4.6 years (range 0.5-7.8). RESULTS: Kidney function loss occurred in 57 of 172 (33%) patients. Baseline lower eGFR, non-first kidney biopsy, and higher National Institutes of Health (NIH) chronicity index were associated with eGFR loss. Chronicity index was the strongest predictor, but no clear threshold defined higher risk. NIH activity index and International Society of Nephrology (ISN) class were not predictive. Proteinuria at 12 months was prognostic, with urine protein-to-creatinine ratio