Abstract
Purpose :
To explore changes in diabetic retinopathy (DR) through 5 years among eyes assigned to ranibizumab in Protocol I (DRCR.net) to manage diabetic macular edema (DME).
Methods :
DRCR.net Protocol I participants assigned to ranibizumab (N=346) received treatment following a structured re-treatment protocol for a period of 5 years. DR severity was assessed from clinical examination and annual fundus photographs. Standardized definitions for DR improvement and worsening (based on the Early Treatment Diabetic Retinopathy Study DR severity scale and development of proliferative diabetic retinopathy outcomes) were used to calculate the percentage of eyes that improved at annual examinations and the cumulative probability of worsening during the 5-year follow-up.
Results :
Among 235 participants with non-proliferative retinopathy (NPDR) at baseline, the percentages of eyes with retinopathy improvement at the 1-, 3-, and 5- year visits were 29%, 28% and 32% and the corresponding percentages were 38%, 35% and 23% among 111 participants with proliferative retinopathy (PDR) at baseline. Mean (SD) numbers of ranibizumab injections among eyes with NPDR were 8.1 (2.5), 2.2 (2.6), and 1.8 (2.6) in year 1, 3, and 5 respectively, with the corresponding means of 9.0 (2.8), 2.3 (2.9) and 1.7 (2.6) within the PDR group. At each annual visit, eyes that received more injections were more likely to demonstrate retinopathy improvement (P<0.05). The 5-year cumulative probability of worsening was 18% (95% CI: 14%, 25%) and 31% (95% CI: 23%, 42%, P = 0.01) among NPDR and PDR eyes, respectively. The annual rate of worsening did not significantly change throughout the 5-year follow-up period in both DR subgroups.
Conclusions :
Individuals managed with anti-VEGF therapy for DME may simultaneously have favorable alterations in the evolution of their retinopathy. Overall rates of DR improvement and worsening appeared stable over the 5-year follow-up period, suggesting that the dramatic reduction in ranibizumab dosing in years 3 through 5 in Protocol I did not substantially alter these DR outcomes.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.