The association between Uric Acid and Diabetic Retinopathy: Review and meta-analysis

Background: Diabetic retinopathy (DR) is a serious neuro-microvascular complication of diabetes mellitus (DM), which is due to the disturbance of metabolism. Uric acid (UA) is one of the most important indicators of the occurrence and development of metabolism disorders. Many studies reported UA in DR patients was higher than that in non-DR patients. however, the results are controversial. The purpose of this meta-analysis study was to reveal the relationship between UA level and DR. Method We searched the online electronic database and retrieved all the relevant articles published before March 2022. Demographic data and UA biochemical parameters in different studies were collected. The pooled standard mean deviation (SMD) and its 95% confidence interval (CI) were calculated and meta-analysis was performed. Results A total of 32 articles including 20658 patients were involved in this meta-analysis. The UA levels in DR group was significantly higher than that in non-DM group and NDR group ( P  = 0.0001; P  < 0.00001, respectively). Subgroup analysis showed that there were significant differences in UA level between NPDR and PDR groups ( P  < 0.00001), NPDR and NDR groups ( P  = 0.02). In addition, UA levels were significantly higher in DR group comparing NDR group in plasma ( P  < 0.0001), vitreous ( P  < 0.00001) and aqueous humor ( P  < 0.0001) samples. It was also showed UA level was significantly ascended in DR patients no matterT1DM( P  < 0.00001) and T2DM ( P  < 0.00001). Conclusions The UA level is definitely associated with DR severity. Therefore, increased UA concentration maybe a potential biomarker that distinguishes DR from DM, and elevated UA level implied the gradual progress of DR.