Adopting 3-year screening intervals for sight-threatening retinal vascular lesions in type 2 diabetic subjects...

To report the incidence of sight-threatening vascular lesions in type 2 diabetic subjects without retinopathy after adopting a 3-year interval screening program.

In all, 1,691 type 2 diabetic subjects with no detectable retinopathy in two 50° red-free fundus photographs were scheduled for follow-up with photography 3 years later. Age at diabetes diagnosis was 60 ± 12 years, and known duration of diabetes was 6 ± 6 years. Treatment consisted of diet only (26%), oral agents (54%), and oral agents and/or insulin (20%). Glycated hemoglobin A(1c) was 6.4 ± 1.5%.

Of the 1,322 subjects available for follow-up, 73% were still without retinopathy after 3 years, and 28% had developed mild or moderate retinopathy, but none developed severe nonproliferative or proliferative retinopathy. Macular edema requiring laser coagulation occurred in only one eye.

Three-year retinal screening intervals can be recommended in subjects with mild type 2 diabetes and no retinopathy.