Changes of hard exudates in response to intravitreal injection of ranibizumab and lipid lowering medications in diabetic macular edema

Background Diabetic macular edema (DME) associated with hard exudates (HEs) affect the vision of eyes with diabetic retinopathy. The main therapeutic option is intravitreal anti-vascular endothelial growth factor injection. Aim The aim of this study was to assess the changes in HEs in response to intravitreal ranibizumab (IVR) injections in the eyes with DME and to compare the results to that when adding lipid lowering drugs (Atorvastatin) to the IVR injections. Patients and methods This is a prospective randomized comparative interventional study that was conducted from January 2021 to December 2023. It included 60 eyes of 60 diabetic patients having moderate nonproliferative diabetic retinopathy and DME with HEs. The patients were classified into two groups: group I (30 eyes) who received at least 5 monthly IVR injections 0.5 mg/0.05 ml and oral Atorvastatin (10–20 mg/day) and group II (30 eyes) who received at least 5 monthly IVR injections only. The central macular thickness (CMT) was evaluated at baseline and at 6 and 12 months after the initial intravitreal injection. Results In group I, the CMT significantly decreased from 364.6±101.4 μm at baseline to 265.6±68.3 μm ( P <0.001), while in group II, it significantly decreased from 378.6±134.3 μm at baseline to 351.2±133.3 μm ( P =0.026). Group I showed significantly more reduction in the CMT than group II ( P <0.001). The presence of grade 1 HEs decreased from 90% of the eyes to 43.3% of the eyes in group I ( P <0.001) and from 93.3 to 70.0% of the eyes in group II ( P =0.016). Group I had a significantly higher percentage of eyes with regressed HEs ( P =0.04). The best-corrected visual acuity (LogMAR) improved from 0.68±0.37 to 0.22±0.11 in group I ( P <0.001) and from 0.69±0.37 to 0.44±0.32 in group II ( P <0.001), with group I showing significantly more improvement in best-corrected visual acuity than group II ( P =0.013). Conclusion Adjuvant lipid-lowering therapy with IVR showed additional effect in the management of DME with HEs where there was more significant decrease in the CMT, improvement in grading of HEs, and in visual acuity improvement over the 12-month follow up period.