Protective Effects of Fenofibrate on Retinal Microvasculature in Early Diabetic Retinopathy

Abstract Background: Early-stage diabetic retinopathy (DR) lacks established pharmacologic treatments. Fenofibrate has shown potential in slowing DR progression, but imaging-based evidence of its microvascular effects is limited. This study aimed to evaluate the protective effects of fenofibrate on retinal microvasculature in patients with early-stage DR using optical coherence tomography (OCT) and OCT angiography (OCT-A). Methods: In this single-center, prospective observational study conducted at Ankara City Hospital, 60 patients with mild to moderate nonproliferative DR were followed over 12 months. Group 1 (n = 30) received combined statin and fenofibrate therapy, and Group 2 (n = 30) received statin monotherapy. Changes in OCT parameters [central retinal thickness, ganglion cell complex, retinal nerve fiber layer, choroidal thickness] and OCT-A parameters [superficial and deep capillary plexus, retinal vessel density, choriocapillaris density, radial peripapillary capillary density, and foveal avascular zone] were assessed at baseline, 6 months, and 12 months. Results Over 12 months, Group 1 demonstrated significant preservation of superficial and deep capillary plexus, retinal vessel density, and choriocapillaris density compared with Group 2 (p < 0.05), which showed progressive microvascular deterioration. No significant differences were observed between groups in OCT-derived structural parameters, foveal avascular zone, or radial peripapillary capillary density. Conclusions Fenofibrate was associated with significant preservation of retinal microvascular integrity in early-stage DR, detectable with OCT-A before structural damage occurs. These findings support fenofibrate as a potential pharmacologic option for early intervention in DR.