Endocrine Abstracts

Background and Aims: to assess the relationship between level of interleukin-6 (IL-6) and the renal function in patients with diabetes mellitus (DM).

Method: A total of 416 patients with DM, aged 34 to 75 years, were examined. Control group included 60 healthy patients the same age/All patients underwent standard clinical and laboratory examination, with an assessment of the levels of natriuretic peptides (BNP, proBNP) and level of IL-6. Renal function was assessed based on the levels of serum creatinine, cystatin C, eGFR, which was calculated according to the CKD-EPI formula, and albuminuria, which was assessed as albumin/creatinine ratio. Statistical data analysis was performed using smSTATA 14.2 for Mac (2018).

Results: The levels of IL-6 in patients with DM were higher than in control group (3,14 [1,7;9,1] vs. 1,5 [1,5;1,7] mg/ml). The level of IL-6 increased with GFR decreasing from 1.7 [1.5; 1.9] mg/ml in CKD 1 to 11.4 [8.9; 32.1] mg/ml in CKD 5 and significantly different between all groups. At the same time, IL-6 values in patients with CKD 1 were also significantly higher compared to the control group (1.7 [1.5; 1.9] mg/ml vs. 1.5 [1.5; 1.7], at p<0.001). IL-6 significantly correlated with cystatin C (r=0.71, p<0.001). A strong negative correlation was also observed between IL-6 and eGFR (r=-0.73, p<0.001). Multiple linear regression analysis revealed a significant association of creatinine and IL-6 (ß=0.29, p<0.001). To find the optimal cut-off threshold for reducing eGFR, a classification analysis using ROC curves was used. At the level of IL-6=2.6 mg/ml, the sensitivity and specificity were 76.7% and 73.9%.

Conclusion: IL-6 might be an independent predictor of decreased renal function in patients with diabetes. Further study of the role of pro-inflammatory cytokines in the development of renal impairments will make it possible to finally decode the mechanisms of their pathogenesis, which will further allow us to understand their complex effect on the body and obtain information for the development of new effective and safe specific medicines.