Analysis of clinical characteristics and risk factors of different types of hyperuricemia in patients with type 2 diabetes

Objective To investigate the proportion of different types of hyperuricemia(HUA) and their respective risk factors in patients with type 2 diabetes mellitus. Methods A total of 435 inpatients with normal renal function were enrolled in the Metabolic Disease Hospital of Tianjin Medical University from January to December 2016 by stratified random sampling method. According to serum uric acid, fraction of uric acid excretion (FEUA) and uric acid excretion rate(UEUA), the patients were divided into four groups: normal serum uric acid group, synthesis-increased HUA group, mixed type of HUA group and excretion-decreased HUA group. One-factor analysis of variance(ANOVA) test was used to analyze the general information and biochemical indicators of each group. The independent risk factors of each group were analyzed by multivariate binary logistic regression. Results The overall detection rate of HUA in type 2 diabetes was 20.68% (90/435). The proportions of synthesis-increased HUA was 28% (25/435), mixed type of HUA was 23%(21/435), excretion-decreased HUA was 49% (44/435). The 24 hour urinary uric acid and UEUA in synthesis-increased HUA group were higher than those in normal uric acid group(F=16.496, 40.042, all P<0.05), and the independent risk factors of synthesis-increased HUA group were estimated glomerular filtration rate (OR=0.939, 95%CI: 0.891-0.990, P<0.05), total bilirubin(OR=0.755, 95%CI: 0.594-0.960, P<0.05), and triglyceride(OR=1.215, 95%CI: 1.001-1.473, P<0.05). The 24 h urinary uric acid and UEUA in mixed type of HUA group were higher than those in normal uric acid group (F=16.496, 40.042, all P<0.05), FUEA was lower than that in normal uric acid group (F=22.692, P<0.05), and its independent risk factor was triglyceride (OR=1.230, 95%CI: 1.083-1.396, P<0.01). The 24 hour urinary uric acid, FEUA and UEUA in excretion-decreased HUA group were lower than those in normal uric acid group (F=16.496, 22.692, 40.042, all P<0.05), and its independent risk factor was body mass index(OR=1.163, 95%CI: 1.086-1.247, P<0.001). Conclusions In patients with type 2 diabetes and HUA, about 50% patients are synthesis-increased HUA or mixed type of HUA. Different types of HUA have different characteristics and risk factors, therefore should be treated with different methods. Key words: Type 2 diabetes mellitus; Hyperuricemia; Synthesis-increased hyperuricemia; Excretion-reduced hyperuricemia; Mixed type of hyperuricemia