. Forty-five patients from the era before the availability of erythropoietin were matched to 45 patients from 2002 to 2004 who had been given erythropoietin but had similar prevalence of proliferative retinopathy, neuropathy, and years of diabetes before the onset of end-stage renal disease. Progression of retinopathy was compared according to multivariate analysis with 2-tailed Pearson correlation coefficient.