Serum uric acid to creatinine ratio: A predictor of incident chronic kidney disease in type 2 diabetes mellitus patients with preserved kidney function

Background: Serum uric acid has shown to be a predictor of renal disease progression in most but not all studies. This study aims to test whether renal function-normalized serum uric acid is superior to serum uric acid as the predictor of incident chronic kidney disease in type 2 diabetes mellitus patients. Methods: In this study, 1339 type 2 diabetes mellitus patients with estimated glomerular filtration rate60mL/min/1.73m(2) and normouricemia were included. Renal function-normalized serum uric acid was calculated using serum uric acid/creatinine. Cox regression analysis was used to estimate the association between serum uric acid, renal function-normalized serum uric acid and incident chronic kidney disease. Results: In total, 74 (5.53%) patients developed to chronic kidney disease 3 or greater during a median follow-up of 4years, with older ages, longer diabetes duration and lower estimated glomerular filtration rate at baseline. The decline rate of estimated glomerular filtration rate was positively correlated with serum uric acid/creatinine (r=0.219, p<0.001), but not serum uric acid (r=0.005, p=0.858). Moreover, multivariate analysis revealed that serum uric acid was not an independent risk factor for incident chronic kidney disease (p=0.055), whereas serum uric acid to creatinine ratio was significantly associated with incident chronic kidney disease independently of potential confounders including baseline estimated glomerular filtration rate. Conclusion: serum uric acid to creatinine ratio might be a better predictor of incident chronic kidney disease in type 2 diabetes mellitus patients.