Systemic inflammation and dyslipidemia are associated with retinopathy in type 2 but not in type 1 diabetes

The aim of this study was to investigate risk factors and role of systemic inflammation, dyslipidemia and obesity in development of diabetic retinopathy (DR) in type 1 and type 2 diabetes and determine the differences in risk factors between these two types of diabetes. Eighty-four type 1 and 107 type 2 diabetic patients were included in this cross-sectional study. Diabetes duration, body mass index (BMI) and waist-to-hip ratio (WHR) were assessed. C-reactive protein (CRP), fibrinogen (FIB), glycated hemoglobin (HbA₁c), fasting and postprandial blood glucose (fBG, ppBG), HDL and LDL cholesterol and triglycerides (TG) were determined using routine methods. HbA₁c_median was obtained by statistical analysis of the CroDiabNet data and used as a marker of long-term glycemic control. Albumin excretion rate (AER) was measured in a 24-hour urine collection. Ophthalmologic retinal examination included indirect slit-lamp fundoscopy, color fundus photography according to EURODIAB (EUROpe and DIABetes) protocol and optical coherence tomography. DR was positively related to diabetes duration (p < .001), HbA₁c_median (p < .001) and AER (p = .008) in type 1, and diabetes duration (p < .001), HbA₁c_median (p = .018), AER (p < .001), CRP (p = .048) and TG (p = .041) in type 2 diabetes. Regression analysis showed that diabetes duration (OR 1.20, p = .005) and HbA₁c_median (OR 6.92, p = .007) were the main predictors of DR in type 1, and diabetes duration (OR 1.17, p < .001), fBG (OR 1.45, p = .024) and TG (OR 2.08, p = .025) in type 2 diabetes. In conclusion, systemic inflammation and dyslipidemia are associated with DR in type 2 but not in type 1 diabetes.