Renal dysfunction associated with clinical response to intravitreal conbercept therapy for diabetic macular edema

To investigate the impact of renal dysfunction on clinical response to intravitreal conbercept injection (IVC) for diabetic macular edema (DME).

This retrospective study included a total of 100 eyes from 100 patients with DME treated with IVC with 3+PRN regimen. Based on the estimated glomerular filtration rate (eGFR), the patients were divided into normal renal function group (n=37), impaired renal function group (n=27), and renal insufficiency group (n=36). The main outcome measures were best-corrected visual acuity (BCVA) and central subfield macular thickness (CST). Clinical parameters included blood urea nitrogen, serum creatinine, serum uric acid, glycosylated hemoglobin (HbA1c), and hemoglobin.

The mean follow-up time was 3.9mo. The mean number of IVCs was 2.07±1.22 in the three groups. Mean BCVA improved significantly from 0.81±0.49 logMAR at baseline to 0.72±0.52 logMAR in the three groups at the final visit (P<0.001). Mean CST decreased significantly from 427.85±148.99 µm at baseline to 275.31±108.31 µm at final visit (P<0.001). Patients in the normal renal function group had higher baseline hemoglobin levels and thinner baseline CST than those in the impaired renal function and insufficiency renal function group (all P<0.001). Patients in the normal renal function group had higher baseline hemoglobin levels and thinner baseline CST than those in the impaired renal function and insufficiency renal function group (all P<0.001). The three groups had no differences in baseline HbA1c levels (P>0.05). Good baseline BCVA (logMAR, P=0.001) and thicker baseline CST (P=0.041) were associated with visual acuity improvement. Higher eGFR (P<0.001), hemoglobin (P=0.032) and thicker baseline CST (P=0.017) were associated with macular edema retrogression in the conbercept-treated diabetic patients, which showed better anatomical response to IVC.

Our results indicate that the renal dysfunction is the risk factor associated with the efficacy of IVC for DME.