Abstract: FR-PO0839
Serial Body Weight Does Not Independently Track eGFR or Proteinuria in Primary Glomerular Disease: Longitudinal Findings from CureGN
Session Information
- Glomerular Diseases: Practice and New Concepts Shaping Modern Care
October 23, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Thammavaranucupt, Kanin, Chakri Naruebodin Medical Institute, Bang Phli District, Sa, Thailand
- Demas, Caroline, University of Michigan Michigan Medicine, Ann Arbor, Michigan, United States
- Mariani, Laura H., University of Michigan Michigan Medicine, Ann Arbor, Michigan, United States
Background
Body weight is routinely followed in glomerular disease, but changes over time may reflect edema, treatment exposure, or illness rather than adiposity or kidney risk. We examined whether percent change in body weight from baseline was associated with repeated eGFR and urine protein-creatinine ratio (UPCR) in adults with primary glomerular disease.
Methods
We analyzed prospectively collected CureGN data from adults with biopsy-proven primary glomerular disease. Baseline BMI categories were used to describe clinical profile. Percent change in body weight from baseline was evaluated as a time-updated exposure, scaled per 5% increase, in mixed-effects models for repeated eGFR and UPCR, with random intercepts and slopes for time. Models adjusted for demographic, disease, laboratory, and treatment factors. UPCR was log2-transformed and reported as ratios. Prespecified subgroups included overweight/obesity and FSGS/IgA nephropathy.
Results
Among 1,768 adults, 71.3% were overweight or obese at baseline. Higher baseline BMI was associated with older age, greater cardiometabolic burden, more severe edema, and lower eGFR. In adjusted longitudinal models, lower percent change in body weight was associated with higher baseline weight, older age, diabetes, and mycophenolate mofetil use, whereas higher eGFR was associated with modestly greater weight change. However, weight change was not independently associated with repeated kidney measures. Per 5% increase in body weight from baseline, the adjusted eGFR difference was 0.20 mL/min/1.73 m2 (95% CI, -0.04 to 0.43), and the adjusted UPCR ratio was 0.99 (95% CI, 0.97 to 1.01). Findings were similar in overweight/obesity and FSGS/IgA nephropathy subgroups.
Conclusion
In adults with primary glomerular disease, baseline body size and serial weight change carry different clinical information. Higher BMI identifies greater clinical burden at presentation, but weight change over time does not independently track eGFR or proteinuria after accounting for disease activity and treatment factors. Serial weight should be interpreted with volume status, proteinuria, kidney function, and treatment exposure, rather than as a stand-alone marker of kidney risk.