Assessment of renal function could help explain the treatment response for patients with diabetic macular oedema.
Korean investigators reported that poor kidney function negatively impacts the response to intravitreal bevacizumab injections (Avastin, Genentech Inc.) and intravitreal dexamethasone implantation (Ozurdex, Allergan) in patients with diabetic macular oedema (DMO).
Renal function may be a possible indicator of the patient response to treatment in this population, according to Dr Hyeseong Hwang from the Department of Ophthalmology, Chungbuk National University Hospital, College of Medicine, Chungbuk National University, Cheongju, Korea, and colleagues.
The clinicians reached this conclusion after reviewing the medical records of 117 treatment-naïve patients with DMO patients who were treated with intravitreal injections of bevacizumab. The investigators then classified the patients based on the response to that treatment, and those who were refractory to bevacizumab then received the intravitreal dexamethasone implant.
The patient population then was assessed to identify a relationship between systemic factors and the treatment response to both bevacizumab and dexamethasone.
Dr Hwang reported that among the 117 previously untreated patients with DMO, 61 eyes (52.14%) responded to the bevacizumab injections. An intravitreal dexamethasone implant was inserted in 23 of the 56 eyes were did not respond to the bevacizumab treatment; of these, 17 (73.91%) responded to the dexamethasone implant.
The investigators commented that among the various systemic factors of the patients with diabetes, renal function, i.e., the blood urea nitrogen, creatinine, and estimated glomerular filtration rate values, showed a significant (p<0.05) negative correlation with improvement in the central subfield retinal thickness following treatment.
They also reported that there was no difference in the haemoglobin A1C levels regarding the treatment response to both bevacizumab and dexamethasone.
Based on this work, the authors concluded, “The renal function was significantly worse in patients with a poor response to [bevacizumab and dexamethasone]. Renal function could be used as a possible predictor for treatment response in certain patients with DMO. Furthermore, for patients with DMO with poor responses to anti-vascular endothelial growth factor or steroid treatments, assessment of renal function could help explain the poor treatment response.”