In this study, researchers compared 3 strategies for managing eyes with center-involved diabetic macular edema (DME): aflibercept, laser photocoagulation and observation.
Study design
This randomized controlled trial was conducted at 91 centers across the United States and Canada. Investigators enrolled 702 patients with well-controlled type 1 or type 2 diabetes with center-involved DME and 20/25 vision or better. Eyes were randomized to 2 mg of intravitreal aflibercept (n=226), focal/grid laser (n=240) or observation (n=236).
The aflibercept group received an injection at baseline and were evaluated for repeat injections as frequently as every 4 weeks. The laser and observation groups received aflibercept if visual acuity decreased from baseline by at least 10 letters at any visit or by 5 to 9 letters at 2 consecutive visits. The primary outcome was a reduction in visual acuity of at least 5-letters at 2 years. Researchers also reported Antiplatelet Trialists’ Collaboration adverse events (myocardial infarction, stroke, or vascular or unknown death).
Outcomes
At 2 years, the percentage of eyes with at least a 5-letter visual acuity decrease was similar in the aflibercept (16%), laser photocoagulation (17%) and observation groups (19%). Investigators found comparable reductions in CST across the 3 arms. Sixty patients in the laser photocoagulation group and 80 in the observation group received aflibercept due to a decline in visual acuity.
Fifteen (7%) aflibercept eyes, 13 (5%) laser photocoagulation eyes and 8 (3%) observed eyes had Antiplatelet Trialists’ collaboration vascular event; the difference among groups was not statistically significant.
Limitations
Although the study demonstrated that there was no difference in the treatment arms, the high rate of intravitreal aflibercept in the laser photocoagulation (25%) and observation groups (34%) underscores the importance of close follow up for this subset of patients.
Clinical significance
This study demonstrates that patients with center-involved DME and good vision (VA≥20/25) can be closely monitored without treatment until their vision declines, without compromising their long-term visual acuity outcomes.