Objective: To establish the prevalence of diabetic retinopathy (DR), types and risk factors in a diabetic population in Extremadura.
Methods: A cross-sectional study, with prospective data collection, was performed between 1997 and 2001 on 3,114 randomly selected diabetic patients belonging to 13 Diabetologic Assistance Centers. We evaluated: age, gender, type, treatment, duration of diabetes and blood pressure levels. Two color fundus photographs were taken and ophthalmoscopy was performed on both eyes. Data were analyzed using SPSS (11.5).
Results: The mean age of the patients was 63.8 (SD13.4) years, 7.5% were type 1 diabetics, 31.1% were insulin-treated and 46.0% had elevated blood pressure. Prevalence of DR was 35.7%, macular edema: 5.6% and proliferative DR: 5.3%. Multivariate analysis showed that type 1 diabetics have a DR frequency 1.79 times higher than type 2 diabetics (ORaj 1.79; IC 95% 1.22-2.63; p=0.003). Patients who have been diabetic for 5-10 years have a frequency 2 times higher (ORaj 2.00; IC 95% 1.62-2.45; p<0.001), patients diabetic for more than 15 years have a frequency 5.48 times higher (ORaj 5.48; IC 95% 4.33-6.93; p<0.001) than patients who have been diabetic for less than 5 years. The frequency of DR in patients aged more than 60 years is 23% higher than those under that age. (ORaj 1.23; IC 95% 1.01-1.50; p=0.045).
Conclusions: 37.5% of the diabetic population in Extremadura is affected by diabetic retinopathy. New analyses are necessary in this population to detect the existence of other high risk subgroups in order to reduce these high prevalence levels.