The Wisconsin Epidemiologic Study of Diabetic Retinopathy

The four-year incidence and progression of retinopathy were investigated in a population-based sample of people with diabetes diagnosed at 30 years of age or older. For insulin users, 73 (47%) of the 154 who did not have any retinopathy at the first visit developed it in the four-year interval, and 31 (7%) of the 418 free of proliferative retinopathy developed it. Worsening of retinopathy occurred in a total of 34% (142/418). For nonusers of...