Purpose: To investigate the effect of systemic factors on early treatment response to intravitreal bevacizumab injection (IVBI) and intravitreal dexamethasone implant (IVDI) in patients with diabetic macular edema (DME).
Methods: We reviewed the medical records of 117 treatment naïve DME patients who underwent IVBI. We divided the patients according to their IVBI response. An IVDI was performed in patients with poor response to IVBIs. We investigated the various systemic factors of diabetic patients and examined the relationship between systemic factors and the treatment response to IVBI and IVDI.
Results: In a total of 117 treatment naïve DME eyes, 61 eyes (52.14%) were classified as IVBI responders. An IVDI was performed in 23 of 56 eyes with poor response to IVBI, and 17 eyes (73.91%) had a good response. Among various systemic factors of patients with diabetes, renal function (blood urea nitrogen, creatinine, and estimated glomerular filtration rate) showed a significant negative correlation with central subfield retinal thickness improvement after treatment (P < 0.05). However, there was no difference in HbA1C levels regarding the treatment response to IVBI and IVDI.
Conclusion: Renal function was significantly worse in patients with a poor response to IVBI and IVDI. Renal function could be used as a possible predictor for treatment response in certain patients with DME. Furthermore, for patients with DME with poor responses to anti-vascular endothelial growth factor or steroid treatments, assessment of renal function could help explain the poor treatment response.