Persistent Disease Activity in Patients with Longstanding Glomerular Disease

Abstract Introduction Glomerular diseases are characterized by variable disease activity over many years. We aimed to analyze the relationship between clinical disease activity and duration of glomerular disease. Methods Disease activity in adults with chronic minimal change disease, focal segmental glomerulosclerosis, membranous nephropathy, and immunoglobulin A nephropathy (IgAN; first diagnostic biopsy >5 years before enrollment; Of Longstanding Disease (OLD) cohort, N=256) followed at Columbia University Medical Center (CUMC), was compared with disease activity of an internal and external cohort of patients with first diagnostic biopsy Results No significant differences were detected between the three cohorts in terms of age, sex, serum creatinine, and urinary protein/creatinine ratio. For each GN subtype, disease activity in the OLD cohort was comparable with disease activity in the entire CureGN and the CUMC-CureGN cohort. When limiting our comparisons to disease activity in incident CUMC-CureGN patients (first diagnostic biopsy within 6 months of enrollment), OLD patients demonstrated similar activity rates as incident patients. Conclusion Disease activity did not differ among patients with shorter versus longer duration of disease. Such “survivor” patients, with long-term but persistent disease, are potentially highly informative for understanding the clinical course and pathogenesis of GN and may help identify factors mediating more chronic subtypes of disease.