Along with glycemic control, other factors are known to play a role in the pathogenesis of DR including duration of diabetes, ethnicity, hypertension, and smoking status [28,29]. An association between AMD and DR is possible given the shared risk factors such as obesity, age, dyslipidemia, and a common VEGF pathway thought to contribute to blood-retinal barrier breakdown [30]. This evidence concerns the gene VEGFA and diabetes mellitus.