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Published on: January 25, 2019
Anti-Vascular Endothelial Growth Factor and Panretinal Photocoagulation Use after Protocol S for Proliferative
Amee D Azad1, Evan M Chen2, John Hinkle1
1Byers Eye Institute, Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, California.
Purpose:
To characterize the rates of panretinal photocoagulation (PRP) and anti-vascular endothelial growth factor (VEGF) medications before and after publication of the Diabetic Retinopathy Clinical Research Network protocol S.
Design:
A retrospective, cross-sectional study from January 2012, through September 2019, using a nationally representative claims-based database, Clinformatics Data Mart Database (OptumInsight, Eden Prairie, MN).
Participants:
Eyes newly diagnosed with proliferative diabetic retinopathy (PDR), continuous enrollment, and no prior treatment with PRP or anti-VEGF agents.
Methods:
Interrupted time series regression analysis was performed to identify the annual change in treatment rates before and after the publication of Protocol S (November 2015).
Main Outcome Measures:
Annual rates of anti-VEGF or PRP treatments per 1000 treated eyes with PDR.
Results:
From 2012 through 2019, 10 035 PRP or anti-VEGF treatments were administered to 3685 PDR eyes. Of these, 63.6% (n = 6379) were anti-VEGF agents, and 36.4% (n = 3656) were PRP treatments. Throughout treatment, 88.7% of eyes treated with anti-VEGF received the same agent and 7.7% were treated with both PRP and anti-VEGF agents. Panretinal photocoagulation rates declined from 784/1000 treated eyes in 2012 to 566/1000 in 2019 (pre-Protocol S: β = -32 vs. post-Protocol S: -77; P = 0.005), whereas anti-VEGF rates increased from 876/1000 in 2012 to 1583/1000 in 2019 (β = -48 vs. 161, respectively; P = 0.001). Panretinal photocoagulation rates in diabetic macular edema (DME) eyes did not significantly differ from 474/1000 in 2012 to 363/1000 in 2019 (β = -9 vs. -58 respectively; P = 0.091), and anti-VEGF rates increased from 1533/1000 in 2012 to 2096/1000 in 2019 (β = -57 vs. 187; P = 0.043). In eyes without DME, PRP use declined from 1017/1000 in 2012 to 707/1000 in 2019 (β = -31 vs. -111, respectively; P < 0.001), and anti-VEGF use increased from 383/1000 in 2012 to 1226/1000 in 2019 (β = -48 vs. 140, respectively; P < 0.001).
Conclusions:
Following the publication of Protocol S, PRP rates decreased, while anti-VEGF rates increased. Panretinal photocoagulation rates did not significantly change among eyes with DME. Our findings indicate the impact that randomized controlled trials can have on real-world practice patterns.
