1. Proteinuria Reduction and Kidney Survival in Focal Segmental Glomerulosclerosis
- Author
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Liron Walsh, Jonathan P. Troost, Jeffrey B. Kopp, Richard N. Fine, Debbie S. Gipson, Marva Moxey-Mims, Cathie Spino, Frederick J. Kaskel, Rong Wang, Jennifer J. Gassman, Aaron L. Friedman, and Howard Trachtman
- Subjects
Male ,medicine.medical_specialty ,Adolescent ,Urinary system ,030232 urology & nephrology ,Urology ,Renal function ,urologic and male genital diseases ,Dexamethasone ,Article ,Cohort Studies ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Focal segmental glomerulosclerosis ,medicine ,Humans ,030212 general & internal medicine ,Mortality ,Child ,Glucocorticoids ,Proportional Hazards Models ,Tissue Survival ,Proteinuria ,business.industry ,Proportional hazards model ,urogenital system ,Glomerulosclerosis, Focal Segmental ,Remission Induction ,Mycophenolic Acid ,medicine.disease ,Prognosis ,female genital diseases and pregnancy complications ,Clinical trial ,Treatment Outcome ,Nephrology ,Creatinine ,Cyclosporine ,Disease Progression ,Kidney Failure, Chronic ,Female ,medicine.symptom ,business ,Immunosuppressive Agents ,Cohort study ,Kidney disease ,Glomerular Filtration Rate - Abstract
Rationale & Objective Remission of proteinuria has been shown to be associated with lower rates of kidney disease progression among people with focal segmental glomerulosclerosis (FSGS). The goal of this study was to evaluate whether reductions in proteinuria after treatment are associated with greater kidney survival. Study Design Cohort analysis of clinical trial participants. Setting & Participants Patients with steroid-resistant FSGS enrolled in a randomized treatment trial that compared cyclosporine with mycophenolate mofetil plus dexamethasone. Predictors Reduction in proteinuria measured during 26 weeks after initiating treatment. Outcomes Repeated assessments of estimated glomerular filtration rate (eGFR) and time to a composite outcome of kidney failure or death assessed between 26 weeks and 54 months after randomization. Analytical Approach Multivariable linear mixed-effects models with participant-specific slope and intercept to estimate the association of change in proteinuria over 26 weeks while receiving treatment with the subsequent slope of change in eGFR. Multivariable time-varying Cox proportional hazards models were used to estimate the association of changes in proteinuria with time to the composite outcome. Results 138 of 192 trial participants were included. Changes in proteinuria over 26 weeks were significantly related to eGFR slope. A 1-unit reduction in log-transformed urinary protein-creatinine ratio was associated with a 3.90 mL/min/1.73 m2 per year increase in eGFR (95% CI, 2.01-5.79). This difference remained significant after adjusting for complete remission. There was an analogous relationship between time-varying proteinuria and time to the composite outcome: the HR per 1-unit reduction in log-transformed urinary protein-creatinine ratio was 0.23 (95% CI, 0.12-0.44). Limitations Limited to individuals with steroid-resistant FSGS followed up for a maximum of 5 years. Conclusions These findings provide evidence for the benefit of urinary protein reduction in FSGS. Reductions in proteinuria warrant further evaluation as a potential surrogate for preservation of kidney function that may inform the design of future clinical trials.
- Published
- 2019