This study aims to test the impact of new-generation anti-diabetic drugs, such as SGLT2 inhibitors and DPP-4 inhibitors, on the development of diabetic retinopathy (DR). The study hypothesizes that these drugs have protective effects in diabetic retinopathy by delaying its incidence compared to older agents (including metformin) only. Early intervention is critical, as treatment options for advanced stages of DR are limited in terms of their ability to restore impaired vision and their high associated costs. By focusing on delaying the occurrence of diabetic retinopathy, the investigators aim to reduce the burden of DR and improve the quality of life for diabetic patients.