Risk factors for diffuse and focal macular edema

Abstract

Objective: The epidemiological risk factors for the different forms of diabetic macular edema (focal or diffuse) are not differentiated in the literature. In the present study, the objective was to determine which risk factors influence the appearance of focal or diffuse macular edema. Research, Design, and Methods: A 4-year prospective study in a population of Type II diabetic patients (NIDDM) in three groups, the first with 29 patients with diffuse diabetic macular edema (Group A), the second with 32 patients with focal macular edema (Group B), and the third with 32 patients with diabetic retinopathy but without diabetic macular edema (Group C); the three groups were selected on the basis of sex, age, and duration of diabetes with similar patterns. We studied the following risk factors: treatment of diabetes mellitus by insulin, presence of diastolic blood hypertension, presence of microalbuminuria or diabetic nephropathy, levels of HbA 1c, type of diabetic retinopathy, presence of previous panretinal photocoagulation, and levels of triglycerides and fractions of cholesterol. Results: In discriminant analysis and in order of importance, the epidemiological risk factors for Group A were the following: presence of panretinal laser, diastolic blood hypertension, diabetic nephropathy, and insulin treatment; for group B, the risk factors were the following: insulin treatment, presence of diastolic blood hypertension, and high levels of glycated haemoglobin (HbA 1c); and for group, C the risk factors were the following: diastolic blood hypertension, insulin treatment of diabetes, and high levels of HbA 1c. Conclusions: In the present study, the group of patients with focal macular edema were epidemiologically similar to the group of patients with diabetic retinopathy without macular edema, the group of patients with diffuse macular edema were epidemiologically different.