Abstract: FR-PO1190
Effects of Bariatric Weight Loss on Inflammatory Protein Signatures and Shear Elastographic Evidence of Kidney Injury in Obesity
Session Information
- CKD: Mechanisms - 2
October 25, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: CKD (Non-Dialysis)
- 2303 CKD (Non-Dialysis): Mechanisms
Authors
- Ngoh, Clara Lee Ying, National University Hospital, Singapore, Singapore
- Teo, Boon Wee, National University Hospital, Singapore, Singapore
- Shabbir, Asim, National University Hospital, Singapore, Singapore
- Goh, Jorming, National University of Singapore, Singapore, Singapore
- Chua, Horng-Ruey, National University Hospital, Singapore, Singapore
Group or Team Name
- The ELASTO Study Group.
Background
Bariatric surgery represents a unique human model of accelerated metabolic optimization. Preclinical models have demonstrated improvements in inflammatory correlates of kidney injury after weight loss, although mechanisms in humans are poorly elucidated without kidney biopsies. We detected substantive improvements in estimated glomerular filtration rate (eGFR) in obese patients with CKD, following bariatric surgery. While this suggests attenuated kidney injury with reduced adiposity, creatinine-based eGFR is confounded by lean muscle loss. Novel kidney imaging by shear wave elastography bridges these gaps by quantifying kidney parenchymal stiffness non-invasively.
Methods
We studied 50 CKD patients with obesity planned for bariatric surgery. Shear wave elastography (Axiplorer, Hologic) and inflammatory biomarkers (Olink proteomic assays) were sampled at baseline and 6 months post-surgery. Kidney shear wave scans were performed by 2 independent investigators. The average of 12 measurements was taken.
Results
Absolute GFR demonstrated resolution of hyperfiltration 6 months after bariatric surgery (139 versus 103 ml/min, P =0.005). Despite initial high glomerular filtration rates, baseline kidney stiffness by shear wave elastography pre-surgery was 26.1 ± 6.2 kPa, levels of which based on our previous work, should correlate with CKD stage 3. Kidney stiffness improved 1 year-post surgery to 13.1 ± 6.2 kPa (P =0.008). This correlated with improvements in body mass indices from 40.2 ± 11.2 kg/m2 (baseline) to 26.8 ± 12.5 kg/m2 (post-surgery). 276 plasma proteins were sampled. At 1-year post-surgery, 17 protein biomarkers showed decreased expression, in particular CUB-domain containing protein (CDCP1) and Delta/notch-Like EGF repeat (DNER) (All P <0.0001). Conversely, 3 proteins: Fibroblast growth factor-19 (FGF-19), Chemokine ligand-9 (CXCL9), Chemokine ligand-23 (CCL23) showed increased expression (All P <0.05).
Conclusion
By demonstrating kidney stiffness reversal in parallel with reduction in systemic inflammation following bariatric surgery-induced weight loss, this study advocates for intensive weight loss as a means of attenuating CKD progression. Novel serum and elastographic imaging biomarkers hold potential to surpass traditional eGFR in assessment of metabolic kidney disease.
Funding
- Government Support – Non-U.S.