According to a poster presentation from investigators at the Southern College of Optometry and the Ralph H. Johnson VA Medical Center in Charleston, South Carolina, a patient on semaglutide for 6 months experienced rapid advancement of diabetic retinopathy (DR) requiring prompt retinal referral and intravitreal anti-VEGF injections in both eyes.1 This case study, presented by author Hannah E. Grimes, OD, at the 2026 Optometry’s Meeting of the American Optometric Association, held from June 17-20, in Phoenix, Arizona, adds to a growing body of evidence linking GLP-1 receptor agonist initiation with accelerated DR progression in patients with preexisting retinal disease and suboptimal glycemic histories.
As GLP-1 medications continue to be prescribed at increasing rates for type 2 diabetes and weight management, optometrists are increasingly the first eye care providers to identify retinal sequelae in this population.1 Understanding which patients are at highest risk and when to intensify monitoring has become a practical imperative for ODs who are managing diabetic eye disease.
Case presentation: semaglutide, PDR, and hemorrhagic posterior vitreous detachment
Frequently Asked Questions
What is the risk of diabetic retinopathy worsening with semaglutide?
The SUSTAIN-6 trial found initiating semaglutide was associated with increased DR progression risk, particularly in patients with preexisting retinopathy, longer disease duration, prior insulin use, and history of poor glycemic control.
Why does GLP-1 therapy worsen diabetic retinopathy in some patients?
Rapid reduction in blood glucose levels in patients with chronically poor glycemic control is the most widely cited mechanism. Sudden normalization of blood glucose may temporarily worsen retinal perfusion dynamics and accelerate DR progression in vulnerable eyes.
What should optometrists do when a patient starts GLP-1 therapy?
AOA guidelines recommend a comprehensive dilated eye exam at or shortly after GLP-1 initiation. Patients with preexisting DR, high HbA1c, or a history of poor glycemic control should have more frequent follow-ups over the first 12 to 18 months, and clear referral thresholds should be established with retinal co-management partners in advance.
The presenting patient was a 48-year-old African American male with a history of insulin-dependent type 2 diabetes since 2007, hypertension, iron deficiency anemia, and coronary artery disease, who presented to the emergency department for evaluation of a new floater in the left eye with a duration of 4 days.1 His ocular history included proliferative DR (PDR) in the right eye, severe non-proliferative DR (NPDR), and noncenter-involving diabetic macular edema. He had begun a GLP-1 medication 6 months prior and had a recent hospitalization for semaglutide-induced gastroparesis.
Best-corrected visual acuity was 20/20- OD and 20/20 OS, and a posterior segment examination revealed proliferative DR in both eyes, dot-blot hemorrhages in all 4 quadrants, neovascularization within the arcades, scattered cotton wool spots and preretinal hemorrhages, sclerotic vessels in the superior arcade of the right eye, and a hemorrhagic posterior vitreous detachment in the left eye.1 OCT macula showed no center-involving or non-center-involving DME in either eye.
The diagnosis was hemorrhagic posterior vitreous detachment OS and proliferative DR, and the patient was referred the same day to retinal specialists and subsequently received intravitreal anti-VEGF injections in both eyes.1
Contextual study evidence and OD monitoring recommendations for GLP-1 therapy
The SUSTAIN-6 trial, a cardiovascular outcomes study of semaglutide in patients with type 2 diabetes, found initiating semaglutide was associated with an increased risk of DR progression, particularly in patients with preexisting DR and a longer duration of disease.2 Prior insulin use was found to further elevate the risk. The study authors attributed DR worsening to rapid reduction in blood glucose levels in patients with poor glycemic control, a phenomenon also observed in intensive insulin trials.
Among the 6 patients in SUSTAIN-6 who progressed to requiring intravitreal treatment, 5 had preexisting PDR, consistent with the index case.2 The Semaglutide and Cardiovascular Outcomes in Patients with Type 2 Diabetes study reported similar findings: among 79 patients developing DR complications on GLP-1 therapy, 66 had preexisting retinopathy at baseline.1
American Optometric Association guidelines recommend a baseline comprehensive dilated examination prior to or shortly after GLP-1 initiation.3 At-risk patients, defined as those with more severe DR at baseline, a high HbA1c, a history of poor glycemic control, or those who experience rapid improvement in glycemic control, should receive more frequent follow-up visits during the first 12 to 18 months of GLP-1 therapy. Grimes and colleagues emphasize careful DR grading at or before GLP-1 initiation, closer monitoring for higher-risk patients, and patient education about visual symptoms requiring prompt reporting.
“Interdisciplinary communication is crucial to properly manage patients on GLP-1s or any other rapid glycemic control regimen,” they concluded.1
Optometrists are well-positioned to serve as the early-warning system for GLP-1-associated DR progression, given their role in longitudinal diabetic eye care. When a patient discloses recent GLP-1 initiation and arrives with pre-existing moderate to severe DR, poor prior glycemic control, or a history of rapid HbA1c reduction, the case evidence supports shortening follow-up intervals to less than 6 months and having an explicit referral threshold discussion established in advance with retinal co-management partners.
References
Grimes HE, Denton WJ, Singleton K. Quick advancement from semaglutide initiation to intravitreal injections. Poster presented at: AOA 2026; June 17-20; Phoenix, AZ.
Marso SP, Bain SC, Consoli A, et al. Semaglutide and cardiovascular outcomes in patients with type 2 diabetes. N Engl J Med. 2016;375(19):1834-1844. doi:10.1056/NEJMoa1607141
American Optometric Association. Optometric clinical practice guideline: care of the patient with diabetes mellitus. AOA; 2019. Accessed June 18, 2026. https://www.aoa.org/AOA/Documents/Practice%20Management/Clinical%20Practice%20Guidelines/CPG2.pdf
