Study on the Correlation Between GDF-15 Levels and a Diagnostic Model for Diabetic Retinopathy.

Background and Purpose: Diabetic retinopathy (DR) is a chronic complication that affects approximately one-third of individuals with diabetes and represents a serious threat to vision. In recent years, increasing attention has been given to biomarkers and cytokines related to inflammation for their roles in disease mechanisms. This study is aimed at investigating the association between growth differentiation factor-15 (GDF-15) and the risk of DR in Handan, China, and developing a predictive model based on patients' clinical characteristics. Methods: Between January and July 2024, patients with Type 2 diabetes mellitus (T2DM) treated at Handan Central Hospital were enrolled and classified into two groups: 74 patients without DR (NDR) and 79 with DR. Stepwise regression was used to select variables, and a logistic regression model was constructed to predict the risk of DR. Additionally, 17 healthy individuals (control group, CG) were included to explore GDF-15 distribution across different populations. Results: Compared to the NDR group, patients with DR showed significantly lower levels of HB, ALB, CO2, and 2h-CP and considerably higher levels of DvT, UREA, HDL-C, ApoA-1, and GDF-15. A logistic regression model incorporating six key variables-ALB, ApoA-1, CO2, DvT, 2h-CP, and GDF-15-was developed, yielding an accuracy of 0.936 (95% CI: [0.786, 0.992]), which outperformed the model based solely on GDF-15. Comparison among the three groups showed that GDF-15 levels were highest in the DR group and increased progressively with diabetes severity. Conclusion: GDF-15 levels are significantly associated with the presence and progression of DR. The logistic regression model demonstrates high predictive value, suggesting that GDF-15 may serve as a promising biomarker for the early diagnosis and intervention of DR.