Association of urinary sulfated glycosaminoglycan with kidney function in type 2 diabetes mellitus patients

<ns3:p>Background Renal glomerular endothelial cells contain glycocalyx, a sulfated glycosaminoglycan-rich (sGAG) protective layer that helps selectively filter molecules. Glycocalyx damage caused by chronic hyperglycemia alters the permeability of endothelial, representing early diabetic kidney disease (DKD). Therefore, this study assessed the association between sGAG and chronic kidney disease (CKD) risk in patients with type 2 diabetes mellitus. Methods This cross-sectional study was conducted at the Pasar Minggu and Depok Jaya Primary Health Centers. Blood and urine samples were collected for the measurement of eGFR, HbA1c, UACR, and sGAG. Subjects were categorized into two groups according to their eGFR and UACR, forming the basis of the modified CKD risk criteria: low-risk and moderate-to-high-risk. Results Data from 207 participants were analyzed. There was no linear correlation between the sGAG and eGFR. Interestingly, urinary sGAG was significantly higher in the moderate-to-high-risk group than in the low-risk group (2.45 (0.4 – 13.5) vs 1.99 (0 – 17); <ns3:italic>p</ns3:italic>=0.013) with crude OR 1.140 (95% CI 1.016 – 1.278). However, after adjusting for confounders, sGAG were no longer significantly associated with a higher CKD risk (OR=1.109, 95% CI 0.978 – 1.258). Conclusion The significant difference observed in urinary sGAG levels between moderate-to-high-risk and low-risk subjects suggests that glycocalyx layer breakdown is one of the most important mechanisms in DKD. However, HbA1c level, duration of T2DM, obesity, and female sex interfere with the breakdown mechanism in the initial stage of DKD.</ns3:p>