Fig 1. Description of study participants.

A total of 2,197 adult DM patients who visited ophthalmologic clinic at Kangnam Sacred Heart Hospital was screened. Among them, 17 patients were type 1 DM, 49 did not received retinal exam, 8 was diagnosed as hypertensive retinopathy, 6 already was blind, 6 had artificial eyes, and 1 had retinal vein occlusion. Another 400 patients were not available for serial renal function data over 1 year and 118 subjects were already in the advanced stage of chronic kidney disease (stage 4 and 5). Therefore, after excluding 605 patients, a total of 1,592 subjects were included in the final analysis for renal outcome.