Incidence and progression of diabetic retinopathy in low income populationof Mexico City

Diabetic retinopathy is one of the leading causes of preventable blindness in working age population. Diabetes mellitus and this microvascular complication affects frequently Me xican population and presents itself in severe clinical forms. There are no incidence studies of diabetic retinopathy in Mexico. The four year inciden ce and progression of diabetic retinopathy were investigated in low income diabetic patients of Mexico City. In the follow up phase we studied 164 pat ients, 76.6% of the patients studied at baseline, 63 were men and 101 women . All participants had a complete ophthalmological exam and seven field ste reo photographs. All photographs were graded using internationally accepted criteria in the reading center of our institution. The four year incidence of any level of retinopathy was 22.5%. Worsening of retinopathy occurred i n 20.6% and the proliferative diabetic retinopathy stage was reached in 4.5 %. Incidence of diabetic retinopathy was associated to age at diagnosis of diabetes mellitus of less than 45 years and progression was associated to d uration of disease of more than ten years. The four year incidence of macul ar edema was 8.8%. These data are important to plan strategies for preventi on of blindness and the implementation of optimal care of diabetic patients in our country.