Study Finds Increased Risk of Serious Eye Disease in Diabetes Patients Using GLP-1 Drugs

A recent study published in JAMA Ophthalmology has revealed that diabetes patients who use GLP-1 receptor agonists (GLP-1 RAs) may face a higher risk of developing a serious eye condition. The research, conducted by University of Toronto scientists, found that these patients were twice as likely to develop neovascular age-related macular degeneration (nAMD) compared to those not taking GLP-1 drugs.

Study Details and Findings

The study evaluated health data from 139,002 diabetes patients in Canada, all aged 66 years or older. Researchers compared more than 46,000 patients who had used GLP-1 drugs for over six months against 92,668 patients who had not used these medications.

Over a three-year follow-up period between 2020 and 2023, 0.2% (93 patients) of those in the GLP-1 group were diagnosed with nAMD, compared to 0.1% (88 patients) in the non-GLP-1 group. While the overall risk of developing nAMD remained low regardless of GLP-1 usage, the risk increased for patients who had been on GLP-1 drugs for longer periods.

The vast majority (97.5%) of patients in the GLP-1 group were taking Novo Nordisk's semaglutide, marketed as Wegovy, Ozempic, and Rybelsus, while the remaining 2.5% were on Sanofi's lixisenatide.

Implications for Ocular Safety

This study adds to a growing body of literature raising concerns about the potential ocular safety of systemic GLP-1 RA use in diabetes patients. The researchers emphasized that their findings demonstrate associations rather than cause and effect.

AMD is a leading cause of irreversible blindness in older adults, affecting approximately 196 million people as of 2020. While the more common atrophic (dry) form of AMD exists, the neovascular (wet) form studied here is more severe and often leads to rapid, permanent vision loss.

These findings follow another recent study that linked GLP-1 drugs, particularly semaglutide, to an increased risk of nonarteritic anterior ischemic optic neuropathy (NAION), another serious eye condition causing vision loss. That study, also published in JAMA Ophthalmology, found that people taking semaglutide for diabetes or weight loss were four to nearly eight times as likely to develop NAION.

Despite these concerns, pharmaceutical giants Eli Lilly and Novo Nordisk continue to expand their presence in the diabetes and obesity market, including the development of potential oral versions of their popular GLP-1 medicines.