Blood pressure is associated with diabetic retinopathy in type 1 but not in type 2 diabetes

The aim of this study was to investigate the role of systolic blood pressure (SBP) and diastolic blood pressure (dBP) in the development of diabetic retinopathy (dr) in type 1 and type 2 diabetes and to determine the differences between these two types of diabetes. This cross-sectional study included 84 patients with type 1 diabetes (t1dM) and 107 patients with type 2 diabetes (t2dM). Ophthalmologic retinal examination included indirect slit-lamp fundoscopy, color fundus photography according to eurOdiAB (eurOpe and diABetes) protocol and optical coherence tomography. Blood pressure was measured with a mercury sphygmomanometer after a 10-minute rest period. in t1dM, dr was positively associated with SBP (p = 0.035), hbA1c median (p < 0.001) and hypertensive retinopathy (p < 0.001), while in t2dM dr was positively related only to hbA1c median (p = 0.021). Binary logistic regression analysis (no dr/dr) showed that diabetes duration and hbA1c median were the main predictors of dr in both types of diabetes. in contrast, SBP (Or = 1.05, p = 0.045) and hypertensive retinopathy (Or = 3.75, p < 0.001) were the main predictors/indicators of dr only in t1dM. in conclusion, blood pressure is associated with dr in type 1 but not in type 2 diabetes.