A prospective study was devoted to the spontaneous course of diabetic retinopathy. The retinas of 459 diabetics were photographed every two years for a total follow-up period, planned beforehand, of eight years.
For two-year intervals progression of retinopathy was found in 14 to 29 per cent, a stationary picture in 60 to 69 per-cent, and amelioration in 7 to 17 per cent of cases. For four-year intervals these percentages were 32 to 39, 47 to 57, and 10 to 12, for six-year intervals 39–50, 40–47, and 10–14, respectively. During the total eight-year period, 48 per cent progressed, 38 per cent remained stationary, and 14 per cent improved. When the patients in whom retinopathy developed during the investigation were included, the percentages changed numerically without altering the general trend. The influence of the dropout of patients on the results is emphasized.
The results are compared with the results of other prospective studies.
