The Predictors of Early Treatment Effectiveness of Intravitreal Bevacizumab Application in Patients with Diabetic Macular Edema

The aim of this study was to establish whether multiple blood parameters might predict an early treatment response to intravitreal bevacizumab injections in patients with diabetic macular edema (DME). Seventy-eight patients with non-proliferative diabetic retinopathy (NPDR) and DME were included. The treatment response was evaluated with central macular thickness decrease and best corrected visual acuity increase one month after the last bevacizumab injection. Parameters of interest were the neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), vitamin D, and apolipoprotein B to A-I ratio (ApoB/ApoA-I). The NLR (2.03 +/- 0.70 vs. 2.80 +/- 1.08; p < 0.001), MLR (0.23 +/- 0.06 vs. 0.28 +/- 0.10; p = 0.011), PLR (107.4 +/- 37.3 vs. 135.8 +/- 58.0; p = 0.013), and SII (445.3 +/- 166.3 vs. 675.3 +/- 334.0; p < 0.001) were significantly different between responder and non-responder groups. Receiver operator characteristics analysis showed the NLR (AUC 0.778; 95% CI 0.669-0.864), PLR (AUC 0.628; 95% CI 0.511-0.735), MLR (AUC 0.653; 95% CI 0.536-0.757), and SII (AUC 0.709; 95% CI 0.595-0.806) could be predictors of response to bevacizumab in patients with DME and NPDR. Patients with severe NPDR had a significantly higher ApoB/ApoA-I ratio (0.70 (0.57-0.87) vs. 0.61 (0.49-0.72), p = 0.049) and lower vitamin D (52.45 (43.10-70.60) ng/mL vs. 40.05 (25.95-55.30) ng/mL, p = 0.025). Alterations in the NLR, PLR, MLR, and SII seem to provide prognostic information regarding the response to bevacizumab in patients with DME, whilst vitamin D deficiency and the ApoB/ApoA-I ratio could contribute to better staging.