Treatment patterns and outcomes of first lupus nephritis episode over 25 years in two Latin American cohorts

Objectives: To compare the treatments used for the first episode of lupus nephritis (LN) in two Latin American cohorts (historical and contemporary) over a 25-year period, and their associations with clinical outcomes. Methods: Patients with biopsy-confirmed first LN episode were classified as non-proliferative (class V) or proliferative (classes III/IV). Sociodemographic, clinical, and treatment variables were described. Propensity score matching was used to examine the associations with four outcomes: mortality, damage accrual (SDI), hospitalization, and end-stage renal disease (ESRD). Results: A total of 532 SLE patients were included: 362 from GLADEL 1.0 (historical cohort) and 170 from GLADEL 2.0. (contemporary). Compared to GLADEL 1.0, patients in GLADEL 2.0 received lower doses of oral glucocorticoids (GC), more frequently GC pulses and antimalarials but less frequently cyclophosphamide. An increase in the use of mycophenolate mofetil and other immunosuppressants was also observed. In the logistic regression models, SDI was associated with baseline SDI and GC pulses, whereas belonging to the GLADEL 2.0 was a protective factor. Mortality was associated with Mestizo ethnicity and partial health coverage; antimalarial was identified as a protective factor. Hospitalizations were associated with baseline SLEDAI and SDI, follow-up time, and lower educational level. Belonging to the GLADEL 2.0 cohort was protective against the occurrence of ESRD. Conclusions: Patients in the contemporary cohort benefited from advances in treatment strategies, with less cumulative damage and progression to ESRD, although mortality remained unchanged. These improvements likely reflect the increased use of newer therapies, more targeted approaches, in line with current treatment guidelines, and better access to specialized care.