Other variables associated with DR were lower education, OR 1.08 for primary versus college/university (95% CI 1.02 to 1.14, p=0.009), previous stroke, OR 1.18 (95% CI 1.07 to 1.30, p=0.001), CKD, OR 1.29 (95% CI 1.07 to 1.56, p=0.008), treatment with acetylsalicylic acid, OR 1.14 (95% CI 1.07 to 1.21, p<0.001), ACE inhibitors, OR 1.12 (95% CI 1.05 to 1.19, p<0.001), and alpha blockers, OR 1.41 (95% CI 1.15 to 1.73, p<0.001). This evidence concerns the gene ACE and chronic kidney disease.