The Impact of Laboratory Findings and Optical Coherence Tomography Biomarkers on Response to Intravitreal Anti-VEGF Treatment in Patients with Diabetic Macular Edema

Abstract

ABSTRACT Purpose To investigate potential laboratory and imaging biomarkers as treatment response predictors to intravitreal anti-vascular endothelial growth factor (anti-VEGF) agents in patients with diabetic macular edema (DME). Methods The study included 36 treatment naïve patients with DME, treated with intravitreal anti-VEGF agents and followed-up for 12 months. At baseline, all participants underwent best-corrected visual acuity (BCVA) measurement, dilated fundoscopy, optical coherence tomography, color fundus photography and fluorescein angiography, while full blood count and biochemical analysis of various parameters was also performed. At month 12, treatment response was examined and classified as “favorable” or “non-response”. Potential associations between laboratory/imaging biomarkers and treatment response were assessed. Results Univariate analysis showed that favorable response at month 12 after initiation of anti-VEGF treatment was correlated with baseline central subfield thickness (CST)≤405 μm (p < .001), absence of subretinal fluid (p = .034), absence of exudates (p = .041), absence of disorganization of the inner retinal layers (p = .037), intact ellipsoid zone (EZ) and external limiting membrane (ELM) (p < .001 and p = .002, respectively), absence of epiretinal membrane (ERM) (p = .040) and absence of macular ischemia (p = .042), while increased lipoprotein(a) was associated with no treatment response (p = .025). At the multivariate analysis, CST was found to be independent predictor of treatment response, while EZ, ELM and ERM were found to predict treatment response perfectly and they could not be entered in the model. Conclusion Intact EZ and ELM, absence of ERM and CST≤405 μm at baseline can predict favorable treatment response in patients with treatment naïve DME, while no correlation with baseline laboratory parameters was found.