RISK-FACTORS FOR HIGH-RISK PROLIFERATIVE DIABETIC-RETINOPATHY AND SEVERE VISUAL-LOSS - EARLY TREATMENT DIABETIC-RETINOPATHY STUDY REPORT NUMBER-18

PURPOSE. TO identify risk factors for the development of high-risk pro liferative diabetic retinopathy (PDR) and for the development of sever e visual loss or vitrectomy (SVLV) in eyes assigned to deferral of pho tocoagulation in the Early Treatment Diabetic Retinopathy Study (ETDRS ). METHODS. Multivariable Cox models were constructed to evaluate the strength and statistical significance of baseline risk factors for dev elopment of high-risk PDR and of SVLV. RESULTS. The baseline character istics identified as risk factors for high-risk PDR were increased sev erity of retinopathy, decreased visual acuity (or increased extent of macular edema), higher glycosylated hemoglobin, history of diabetic ne uropathy, lower hematocrit, elevated triglycerides, lower serum albumi n, and, in persons with mild to moderate nonproliferative retinopathy, younger age (or type 1 diabetes). The predominant risk factor for dev elopment of SVLV was the prior development of high-risk PDR. The only other clearly significant factor was decreased visual acuity at baseli ne. In the eyes that developed SVLV before high-risk proliferative ret inopathy was observed, baseline risk factors were decreased visual acu ity (or increased extent of macular edema), older age (or type 2 diabe tes), and female gender. CONCLUSIONS. These analyses supported the vie w that the retinopathy-inhibiting effect of better glycemic control ex tends across all ages, both diabetes types, and all stages of retinopa thy up to and including the severe nonproliferative and early prolifer ative stages and the possibility that reducing elevated blood lipids a nd treating anemia slow the progression of retinopathy.