Intractable diabetic macular edema (DME) poses a long-term challenge to patients and doctors alike. In a recent study, researchers investigated the various systemic factors of diabetic patients and examined the relationship between those and how the individuals responded to two common  intravitreal therapies: anti-VEGF and dexamethasone; the study used bevacizumab and the dexamethasone implant Ozudex, respectively.

The medical records of 117 treatment-naïve DME patients who underwent bevacizumab injection were reviewed and divided according to their response, and Ozudex was performed in patients who responded poorly to the anti-VEGF.

Overall, renal function was significantly worse in patients who responded poorly to both interventions. Among various systemic factors of patients with diabetes, renal function (assessed by levels of blood urea nitrogen, creatinine and estimated glomerular filtration rate) showed a significant negative correlation with central subfield retinal thickness improvement after treatment.

The team concluded that renal function could affect anatomical improvement after bevacizumab in patients with DME, and that renal function may also affect response to dexamethasone. “Therefore, renal function may be used as a possible predictor for the treatment response of certain patients with DME. In the case of patients with DME with poor response to anti-VEGF or steroid treatments, assessment of renal function could provide a clue for understanding the poor treatment response.

“By improving renal function, if possible, we may presume that the treatment response of patients with DME to anti-VEGF or steroid injections could eventually be improved.”