AIM: To explore the predictive value of the combination of triglyceride-glucose(TyG)index, nesfatin-1, and retinol-binding protein 4(RBP4)for diabetic retinopathy, and provide evidence for early prediction of DR.

METHODS: The clinical data of 164 patients with type 2 diabetes mellitus(T2DM)who admitted to the hospital between February 2022 and December 2023 were retrospectively collected. Based on the fundus examination results, these patients were divided into two groups: the DR group(n=43), including proliferative DR(PDR, n=19)and non-proliferative DR(NPDR, n=24), and the T2DM without DR group(n=121). The TyG index and the level of nesfatin-1 and RBP4 were measured after admission.

RESULTS:T2DM patients with DR had a longer disease duration compared with T2DM patients without DR, and the DR group had higher fasting blood glucose, glycosylated hemoglobin, triglyceride, total cholesterol, low-density lipoprotein, TyG index, and RBP4 levels, while lower high-density lipoprotein and nesfatin-1 levels(all P<0.001). Multivariate Logistic regression analysis indicated that the duration of T2DM(OR=1.338, 95%CI: 1.059-1.690), glycosylated hemoglobin(OR=5.065, 95%CI: 1.659-15.470), low density lipoprotein(OR=12.715, 95%CI: 2.385-67.790), TyG index(OR=23.057, 95%CI: 2.936-181.073)and RBP4(OR=1.319, 95%CI: 1.028-1.692)were the independent risk factors for DR, while nesfatin-1(OR=0.007, 95%CI: 0.003-0.016)was an independent protective factor for DR. The ROC curves were drawn, and the results indicated that the TyG index, nesfatin-1, and RBP4 had certain predictive values for DR patients with T2DM, with areas under curve(AUC)of 0.804, 0.878 and 0.738, respectively. The combined AUC of the TyG index, nesfatin-1, and RBP4 was 0.946, sensitivity was 83.72%, and specificity was 92.56%. Patients with PDR had a higher TyG index, higher RBP4 level, and lower nesfatin-1 level than patients with NPDR(all P<0.05). Spearman's correlations indicated a positive association between the TyG index, RBP4 and DR degree, and a negative association between nesfatin-1 and DR degree(r_s=0.557, 0.392, -0.359, repectively, all P<0.05). Pearson correlation analysis indicated a negative correlation between the TyG index and the levels of nesfatin-1, a positive correlation between the TyG index and the levels of RBP4, and a negative correlation between the levels of nesfatin-1 and RBP4 in DR patients with T2DM(r=-0.486, 0.538, -0.592, all P<0.05).

CONCLUSION: The serum of TyG index and the levels of nesfatin-1 and RBP4 were early predictive markers for DR and were associated with the risk of the occurrence and severity of the disease. Besides, the combined prediction performance of TyG index, nesfatin-1, and RBP4 was better for DR.