AIM: To investigate the expression and clinical significance of Toll-like receptor 4(TLR4)and vascular endothelial growth factor A(VEGFA)in the serum of patients with diabetic retinopathy(DR).

METHODS: A total of 183 patients with type 2 diabetes mellitus(T2DM)admitted to our hospital from January 2021 to January 2022 were collected as the study subjects. They were grouped into non diabetic retinopathy(NDR)group(n=54), proliferative diabetic retinopathy(PDR)group(n=68)and non proliferative diabetic retinopathy(NPDR)group(n=61). In the same period, 70 volunteers who underwent physical examination in our hospital were randomly stratified according to age and sex. After discharge, DR patients were followed up for 1a and grouped into a poor prognosis group(n=40)and a good prognosis group(n=89)based on whether they had visual impairment. Enzyme-linked immunosorbent assay(ELISA)was applied to detect the levels of TLR4 and VEGFA in serum; Logistic regression was applied to analyze the influencing factors of DR; receiver operating characteristic(ROC)curve was applied to analyze the clinical value of serum TLR4 and VEGFA levels in diagnosing DR and predicting prognosis.

RESULTS: There were statistical significance in TLR4 and VEGFA levels among the control group, NDR group, PDR group, and NPDR group(F=935.753, 516.936, all P<0.05), and further pairwise comparisons showed statistical significance(P<0.05); the expression levels of TLR4 and VEGFA in the serum of patients with poor prognosis were higher than those of patients with good prognosis(P<0.01); the results of Logistic regression analysis showed that TLR4, VEGFA, course of disease, and HbA1c were all risk factors for the occurrence of DR(P<0.05); the ROC results showed that the AUC of serum TLR4, VEGFA levels, and their combination for predicting DR was 0.869, 0.862, and 0.931, respectively, the AUC of serum TLR4, VEGFA levels, and their combined prediction of visual disability in DR patients was 0.864, 0.863, and 0.938, respectively.

CONCLUSION: The expression of TLR4 and VEGFA in serum of DR patients is up-regulated, and the combined detection of TLR4 and VEGFA can be used as a potential indicator to evaluate the occurrence and poor prognosis of DR.