Immature granulocytes as a biomarker for diabetic retinopathy progression without anti-VEGF therapy: A cross sectional study

Background Diabetic retinopathy (DR) is one of the most common complications of diabetes and is the leading cause of low vision and blindness worldwide. Objective The present study aimed to evaluate delta neutrophil index (DNI), the immature granulocyte count (IG#), and percentage (IG%) in the diabetic group without retinopathy and in the diabetic group with DR. Methods A total of 175 participants were diagnosed with diabetes mellitus (DM (non-DR), 128 patients were diagnosed with nonproliferative diabetic retinopathy (NPDR) (n = 89), and one was diagnosed with diabetic proliferative retinopathy (PDR) (n = 39). Results The level of GR# and GR% in PDR was statistically significant than non-DR and NPDR (P = 0.03 and p = 0.02, respectively). The sensitivity and specificity of GR# and GR% for predicting progression from NPDR to PDR were determined to be 66.7% and 44.9%, respectively (area under curve [AUC] = 0.621, p = 0.029; 95% confidence interval [CI] = 0.512-0.730; and area under curve [AUC] = 0.623, p = 0.027, 95% confidence interval [CI] = 0.517-0.728). Additionally, IG# was not an independent risk factor for DR (p > 0.05). There were no significant differences in DNI among the NDR, NPDR, and PDR groups (p > 0.05). Conclusion IG# and IG% may be promising minimally invasive biomarkers for distinguishing NPDR from PDR but not DNI. We believe that they are markers that need to be confirmed in prospective studies for obtaining more reliable results in the detection of DR.