Risk of Blindness Among Patients With Diabetes and Newly Diagnosed Diabetic Retinopathy
To evaluate association between initial diabetic retinopathy (DR) severity/risk of blindness in patients with newly diagnosed DR/good vision in the U.S.
RESEARCH DESIGN AND METHODS
Retrospective cohort study of adult patients with good vision (20/40 or better)/newly diagnosed DR between 1 January 2013 and 31 December 2017 (index date) in the American Academy of Ophthalmology’s IRIS® Registry. Primary exposure of interest, DR severity at index: mild nonproliferative DR (NPDR), moderate NPDR, severe NPDR, proliferative DR (PDR). Main outcome measure: development of sustained blindness (SB), defined as study eyes with Snellen visual acuity readings of 20/200 or worse at two separate visits ≥3 months apart that did not improve beyond 20/100.
Among 53,535 eligible eyes (mean follow-up, 662.5 days), 678 (1.3%) eyes developed SB. Eyes with PDR at index represented 10.5% (5,629/53,535) of the analysis population but made up 26.5% (180/678) of eyes that developed SB. Kaplan-Meier analysis revealed that eyes with moderate NPDR, severe NPDR, and PDR at index were 2.6, 3.6, and 4.0 times more likely, respectively, to develop SB after 2 years of DR diagnosis versus eyes with mild DR at index. In a Cox proportional hazards model adjusted for index characteristics/development of ocular conditions during follow-up, eyes with PDR had an increased risk of developing SB versus eyes with mild NPDR at index (hazard ratio, 2.26; 95% CI, 2.09−2.45).
CONCLUSIONSIn this longitudinal ophthalmologic registry population involving eyes with good vision, more advanced DR at first diagnosis was a significant risk factor for developing SB.