Abstract:Abstract Objective： To investigate the value of optical coherence tomography angiography (OCTA) parameters and serum caspase-1 for assessing the severity of diabetic retinopathy (DR). Methods： 128 patients(151 eyes) with DR into our hospital from June 2024 to December 2025 were selected in the retrospective study and divided into early non-proliferative DR (NPDR) group (n=75,90 eyes,40 males and 35 females,age of 74.3±5.6 years) and late proliferative DR (PDR) group (n=53,61 eyes,27 males and 26 females,age of 75.9±5.8 years) based on the results of fundus fluorescein angiography (FFA). Additionally, 60 patients(0 eyes,33 males and 27 females,age of 72.6±5.4 years) of diabetes without DR were selected as control group. OCTA parameters, including macular blood flow density, foveal avascular zone (FAZ) circumference and area, mean retinal thickness, hyperreflective dots (HRF) and internal limiting membrane abnormalities among the groups were compared. Blood biochemistry parameters, including fasting blood glucose, glycated hemoglobin (HbA1c), systemic immune-inflammation index (SII), triglyceride/high-density lipoprotein (TG/HDL), urinary albumin-to-creatinine ratio (UACR) and caspase-1 were also compared. Results： Among control group, NPDR group and PDR group, macular blood flow density gradually decreased, while FAZ circumference and area, mean retinal thickness gradually increased, HRF and internal limiting membrane abnormalities gradually increased, SII, UACR and caspase-1 levels gradually increased,too (P<0.05). The duration of diabetes in NPDR group and PDR group were longer than control group (P<0.05). Multivariate logistic regression showed that duration of diabetes, HRF and caspase-1 level were the risk factors to occurrence of DR, while macular blood flow density was protective factor (P<0.05),caspase-1 level was risk factor to progression of DR to PDR, macular blood flow density was protective factor (P<0.05). Receiver operating characteristic (ROC) curve showed that area under curve (AUC) of caspase-1 combined with macular blood flow density for predicting occurrence of DR and PDR were 0.864 and 0.890, respectively, both higher than single indicators (P<0.05). Conclusion： The combination of macular blood flow density from OCTA parameter and serum caspase-1 has important clinical value in assessing severity of DR.
