Trajectories of long-term eGFR and proteinuria in lupus nephritis: a real-world biopsy-proven cohort study

BACKGROUND: The long-term trajectories of estimated glomerular filtration rate (eGFR) and their relation to early proteinuria trajectories in biopsy-proven lupus nephritis (LN) are unclear. We aimed to identify eGFR trajectories and examine their association with 24-hour urine protein (24hUP) trajectories. METHODS: In this retrospective single-centre cohort, 215 adults with class III/IV (±V) LN were followed from the date of their initial renal biopsy. eGFR and 24hUP trajectories were modelled using latent class trajectory models, and associations with clinical and pathologic features were assessed. Multinomial logistic regression was used to identify baseline predictors of trajectory membership. RESULTS: Three eGFR trajectories were identified: stable (87.9%), late-decline (7.0%) and persistent-decline (5.1%). Persistent-decline patients had a higher chronicity index (p