Objective: To report the 6-year incidence of visual loss and associated risk factors in African Americans with type 1 diabetes mellitus.
Methods: African Americans with type 1 diabetes (n=483) who participated in the New Jersey 725 study were reexamined as part of a 6-year follow-up. Best-corrected visual acuity, a structured clinical interview, fundus photographs, and blood pressure measurements were obtained. The biological evaluation included blood and urine assays. Any visual loss was defined as a visual acuity of 20/40 or worse in the better eye, blindness as a visual acuity of 20/200 or worse in the better eye, and doubling of the visual angle (DVA) as the loss of 15 or more letters between the first and second visits.
Results: Over 6 years, 19 of 440 patients (4.3%) developed visual loss in the better eye, 3 of 472 patients (0.6%) became blind, 47 of 481 patients (9.8%) developed DVA in the better eye, and 65 of 481 (13.5%) developed DVA in either eye. Baseline older age, high glycosylated hemoglobin level, retinopathy severity, and proteinuria were characteristics significantly (P<.001 for all) and independently associated with DVA in either eye at follow-up.
Conclusions: The 6-year incidence of DVA in either eye (13.5%) is high in African Americans with type 1 diabetes. Baseline poor glycemic control, diabetic retinopathy severity, proteinuria, and older age are predictors of visual loss in this population.