IDF21-0282 Association between Serum Uric Acid and Renal Outcome in Patients with Biopsy-confirmed Diabetic Nephropathy

Abstract

Background: It is well established that diabetic nephropathy (DN) is the first cause of end-stage renal disease (ESRD) in developed and developing countries. Serum uric acid (SUA) level has been widely recognized as a risk factor for DN development because oxidants are produced that can play a key role in renal injury during UA synthesis. Recently, a randomized, controlled trial (RCT) showed that in Multi-ethnic patients with a high risk of progression and stage 3-4 CKD in Australia and New Zealand, SUA lowering treatment using allopurinol could not significantly attenuate the drop of eGFR as compared with placebo, which is somewhat intriguing. Therefore, the association between SUA and renal outcome in type 2 diabetes mellitus (T2DM) and DN patients remains to be elucidated in more detail. Aim: To investigate the relationship between SUA level and renal outcome in patients with T2DM and diabetic nephropathy (DN). Method: A total of 393 Chinese patients with T2DM and biopsy-proven DN and followed at least one year were enrolled in this study. Patients were stratified by the quartiles of baseline level of SUA: Q1 group286.02± 46.66 μmol/L (n=98); Q2 group: 358.23±14.03 μmol/L (n=99); Q3 group: 405.50±14.59 μmol/L (n=98) and Q4 group: 499.14±56.97 μmol/L (n=98). Renal outcome was defined by progression to end stage renal disease (ESRD). Kaplan-Meier survival analysis and Cox proportional hazards model were used to analyze the association between SUA quartiles and the renal outcomes. Results: During the median 3-year follow-up period, there were 173 ESRD outcome events (44.02%) during follow-up. No significant difference among SUA level the risk of progression of DN (P=0.747) was shown in the Kaplan-Meier survival analysis. In multivariable-adjusted model, HRs for developing ESRD were 1.364(0.621-2.992; p=0.439), 1.518(0.768-3.002; p=0.230) and 1.411(0.706-2.821; p=0.330) for the Q2, Q3 and Q4, respectively, in comparison with the Q1 (P=0.652). Discussion: No significant association between SUA level and renal outcome of ESRD in Chinese patients with T2DM and DN was found in our study. Besides, the role of uric acid-lowering therapy in delaying DN progression and improve ESRD outcome had not yet been proven. Further study was needed to clarify the renal benefit of the uric acid-lowering therapy in the treatment of DN.