Combined effect of glycemic and blood pressure control on diabetic retinopathy among Chinese with type-2 diabetes mellitus

Abstract Background To explore the associations of glycemic and blood pressure (BP) control with diabetic retinopathy (DR), with special focus on whether different combinations of categories of these two interventions are additive. Methods A community-based survey including 913 patients with known type-2 diabetes mellitus (T2DM) was conducted in Suzhou, China. Retinal photographs were graded for the presence of DR using the Airlie House classification system. BP and blood hemoglobin A1c (HbA1C) levels were measured by standardized protocols. Binary logistic regression models were established to examine the associations of risk factors with DR. Results The overall prevalence of any DR was 18.0% [95% confidence interval (95% CI) 15.5–20.6%] in this population. Stratified by conventional control thresholds, lower levels of either systolic blood pressure (SBP,