Prevalence and Relationship Between Diabetic Retinopathy and Nephropathy, and its Risk Factors in the North-East of Spain, a Population-Based Study

Purpose: To determine the prevalence of microangiopathy, and its risk factors in a population-based study of diabetes mellitus patients in the north-eastern area of Spain. Methods: A population-based transversal study of 8,187 type 2 (83.37% of the diagnosed patients) and 488 type 1 (85.76% of the diagnosed patients) underwent a detailed medical history that included: diagnoses of diabetic retinopathy, macular edema, microalbuminuria or overt nephropathy. A study of its risk factors, and the relationship between diabetic retinopathy and renal lesion was performed. Results: In type 1 diabetes patients we observed a prevalence of 36.47% of diabetic retinopathy and 5.73% with macular edema; in type 2 diabetes patients the prevalence of diabetic retinopathy was 26.11% and 6.44% with macular edema. Microalbuminuria prevalence was 25.61% in type 1 and 17.78% in type 2 patients, and overt nephropathy prevalence was 8.60% in type 1 and 6.74% in type 2 diabetic patients. The risk factors for diabetic retinopathy were: diabetes duration, high glycosylated level, and arterial hypertension, and insulin treatment in type 2. The Total-cholesterol/High Density-cholesterol (TC/HDL) ratio and triglycerides were significant for diabetic macular edema (DME). Microalbuminuria and overt nephropathy were well correlated to diabetes duration, arterial hypertension and glycosylated haemoglobin. Conclusions: Prevalence and risk factors for microangiopathy are similar to other studies, and the important finding is that the TC/HDL ratio was significant for DME. Microalbuminuria is a risk factor for diabetic retinopathy in type 1 diabetes mellitus patients but not for type 2. Overt nephropathy is well correlated with diabetic retinopathy.